Gem module

Do you have a factory or some other type of professional scan tool ? Check for DTC'S - diagnostic trouble code's in the instrument cluster an the GEM - generic electronic module .Before guessing an just replacing parts .

https://www.aa1car.com/library/battery_disconnect_problems.htm

It's hard to say what's wrong without hooking up a factory san tool !
The instrument cluster is a configurable, hybrid electronic cluster (HEC) that contains a microprocessor, gauges, indicator lamps, and internal circuitry. The instrument cluster is non-repairable, with the exception of the instrument cluster lens, the warning bulbs, and the transmission range selector. The instrument cluster uses hardwired circuitry, the controller area network (CAN), and universal asynchronous receiver transmitter (UART)-based protocol (UBP) communication networks. Communication using the CAN uses data transmitted and received between the instrument cluster, the trailer brake control (TBC) electronic control unit, the powertrain control module (PCM), and the anti-lock brake system (ABS) module. Communication using the UBP network uses data transmitted and received by the instrument cluster, the vehicle security module, and the electronic automatic temperature control (EATC). For additional information regarding the communication network, refer to Section 418-00 .
It is very important to understand:

• where the input originates.
• all the information necessary in order for a feature to operate.
• which module(s) receive(s) the input or command message.
• whether the module which received the input controls the output of the feature, or whether it outputs a message over the CAN or UBP network to another module.
• which module controls the output of the feature.

The instrument cluster carries out a display prove-out to verify that the warning/indicator lamps and monitored systems are operating correctly. The safety belt warning indicator proves-out for 65-seconds or until the safety belt is fastened. The malfunction indicator lamp (MIL), and the wait to start indicator (diesel engines) illuminate continuously until the engine is started and operating normally. When the ignition switch is turned to the ON position with the engine off, the following indicators illuminate for 3 seconds:
Odometer The odometer and trip odometer are viewed through the message center in the integrated circuit display on message center clusters or in the integrated circuit display on base clusters. The odometer is tamper-resistant and accumulates and registers up to one million kilometers in metric mode or one million miles in English mode, based upon rolling count data sent from the PCM over the communication network. The trip odometer is resettable and accumulates and registers up to 9,999 kilometers or 9,999 miles.
Does the speedometer work ?
Does

The rear wiper / washers are controlled by the GEM - generic electronic module .
NOTE: The generic electronic module (GEM) will not activate the rear wiper system if either the liftgate or the liftgate glass is ajar. If either the liftgate or the liftgate glass becomes ajar while the rear wiper is in operation, the GEM will park the rear wiper motor.
There are two distinct modes of wiper operation:

• Off Mode: In this mode, there is no rear wiper activity, and the wiper motor will be in the PARK position.
• Interval Mode: This mode is selected when the rear wiper switch is in either the Interval 1 or 2 position. When this mode is selected, the rear wiper motor is driven up onto the glass by activating the rear wiper UP relay. When the wiper motor HIGH/LOW/PARK position input reaches the high position, the UP relay is deactivated and the DOWN relay is activated to reverse the wiper motor direction. When the wiper motor reaches the LOW position, as determined by the HIGH/LOW/PARK position input, the GEM deactivates the DOWN relay and will begin a new wiper cycle 1 to 10 seconds later, depending on the interval position selected.

Inspection and Verification

1. The wiper/washer system is a generic electronic module (GEM) controlled system; refer to Section 419-10 .

1. Verify the customer concern by operating the wiper/washer system.

1. Visually inspect for obvious signs of mechanical and electrical damage.

Visual Inspection Chart Mechanical Electrical

• Hoses to windshield washer pump
• Wiper linkage

• Fuses 6 (5A), 8 (5A), 15 (5A), and 20 (5A)
• Wiring harness
• Loose or corroded connector(s)
• Relays
• Motors
• Multifunction switch
• Washer fluid level switch

1. If the concern remains after the inspection, connect New Generation STAR (NGS) Tester to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the NGS menu. If NGS Tester does not communicate with the vehicle:
   • Check that the program card is properly installed.
   • Check the connections to the vehicle.
   • Check the ignition switch position.

1. If NGS Tester still does not communicate with the vehicle, refer to the New Generation STAR Tester manual.

1. Perform the DATA LINK DIAGNOSTIC TEST. If NGS Tester responds with:
   • CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418-00 .
   • NO RESPONSE/NOT EQUIPPED for generic electronic module (GEM), go to Pinpoint Test M.
   • SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and perform self-test diagnostics for the GEM.

1. If the DTCs retrieved are related to the concern, go to GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.

1. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics. Your best bet is take this to a ASE certified repair shop !

To find out what is draining the battery do a parasitic draw test . How To Perform Parasitic Draw Test EricTheCarGuy Test to be sure , before replacing GEM module .I would also have the GEM checked for DTC'S - diagnostic trouble codes . I would also check the battery saver relay .
SECTION 417-02: Interior Lighting 2000 Explorer/Mountaineer Workshop Manual DESCRIPTION AND OPERATION Procedure revision date: 06/17/1999 Interior Lighting The interior lighting system consists of the following:

• dome/map lamp
• rear dome/cargo lamp
• overhead console/map lamp
• RH/LH vanity mirror
• ash receptacle lamp
• puddle lamps
• interior lamp switches
• interior lamp relay
• dimmer module
• battery saver relay
• generic electronic module (GEM)

Generic Electronic Module (GEM)/Central Timer Module (CTM) Controlled Functions
The generic electronic module (GEM) is equipped on four-wheel drive vehicles with power windows. The central timer module (CTM) is equipped only on two-wheel drive vehicles without power windows.
NOTE: GEM/CTM diagnostics are compatible with the scan tool.
The GEM/CTM incorporates the functions of several different modules into one, and offers diagnostics to easily locate and repair concerns affecting the subsystems that it controls.
The GEM/CTM constantly monitors the systems it controls and reports a concern in the form of a diagnostic trouble code (DTC). A DTC can be retrieved with the scan tool through the communication link.
The scan tool is a menu-driven tester that allows the user to run specific tests. The scan tool can isolate faults in the GEM/CTM subsystems through a symptom-driven diagnostic procedure. Connecting the scan tool to the GEM/CTM communication link will not alert the GEM/CTM. If the GEM/CTM is "asleep" when the diagnostic connector is plugged in, the GEM/CTM must be "awakened". If the communication link cannot be established, turn the ignition to RUN.
NOTE: The GEM/CTM has a sleep function to minimize battery consumption. During the sleep mode, the GEM/CTM turns off all outputs and monitors only the following:

• door ajar (driver door, passenger door, liftgate, LH rear and RH rear doors).
• key-in-ignition.
• key in RUN or ACC.
• two-step unlock switch (unarm switch).
• digital TR sensor.
• illuminated entry request (remote anti-theft personality [RAP] module).

If a change of status occurs at one of these inputs while the GEM/CTM is "asleep", the GEM/CTM will "wake up." When the GEM/CTM awakens, it carries out an internal self-test, and begins normal operation. At this point, the GEM/CTM will have all of its functions operational.
The GEM/CTM will go into the sleep mode immediately after both of the following conditions have been met:

• key in OFF or key not in ignition.
• after 45 minutes with no change in any wake-up input.

The GEM/CTM control system has two modes of operation; the normal operating mode and the tester-dependent diagnostics mode.
Normal operation of the GEM/CTM can detect errors. An integral part of normal GEM/CTM operation is continuous diagnostic capability. Continuous diagnostics detects errors and changes the GEM/CTM control strategy. There is no warning lamp for the GEM/CTM; therefore, a DTC concern will direct you to the GEM/CTM. Examples of faults that may be detected during normal operation include:
NOTE: The GEM/CTM can only detect open circuit/short to GRD faults when the GEM/CTM is not energizing a load, and short to battery faults when the GEM/CTM is attempting to energize a load.

• GEM/CTM continuous self-test (RAM, ROM, EEPROM, A/D checking).
• output driver monitoring (open circuit/short to ground [GRD], short to power).

• illogical combinations of input signals.

Check your owners manual for the number 27 fuse to see what it is. Checking online I see it as a 15 Amp, Under hoop lamp, Map lights, Glove box lamp, Dome lamp, Visor lamps, Accessory delay, Dimmer switch illum. and 4x4 system. check each one to see if the bulb is blown but left on, at least if it's a light. It that doesn't do it, research how to check accessory delay and 4x4 system.

. May need to reprogram module due to disconnect.
CAUTION: Prior to removal of the GEM, it is necessary to upload module configuration information to a diagnostic tool. This information needs to be downloaded into the new module once installed. For additional information, refer to Section 418-01.


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The following is list of GEM/CTM-controlled functions:

• wipers/washers (front/rear)
• warning chimes
• battery saver
• illuminated entry and courtesy lamps
• accessory delay
• driver power window (GEM only)

The GEM constantly monitors its subsystems for concerns. If a concern is found in one of the subsystems, the GEM will record the concern in the form of a diagnostic trouble code (DTC). The ignition switch position is very important to the GEM function. Often times, erratic or unexpected GEM function can be traced to concerns with ignition switch inputs.

Principles of Operation:
The generic electronic module (GEM) controls the opening of the driver window by activating the one-touch down window relay.
The GEM controls manual down and auto down window movement with the down window relay. The relay is activated by applying ground directly to one side of the down window relay coil, and deactivated by removing the ground signal. The delayed accessory relay provides power for the operation of the power windows and the roof opening panel (if equipped). The delayed accessory feature is active when the ignition switch is in the RUN or the ACC position, or when the ignition switch is changed from RUN or ACC to the OFF/LOCK position and the driver and passenger doors are closed.
Down window motion operates in two modes, manual mode and auto mode. When the GEM detects the first down position, first detent on the switch, it enters manual mode. In manual mode, the window will move downward only while the switch is depressed. Similarly, when the GEM detects the second down position, second detent on the switch, it enters auto mode. In auto mode, the window will open completely with just a momentary press of the switch.
the GEM will activate the one-touch down window relay until one of the following conditions is met:

• The driver window control switch is pushed to the UP position.
• The driver window control switch is released (OFF position) and then moved to the down position (first detent) or the one-touch down position (second detent).
• Seven seconds have elapsed since the one-touch down feature was initiated.
• A window regulator motor stall condition is detected on the one-touch down sense line inputs.

The GEM will deactivate the delayed accessory feature when:

• the driver/passenger door is ajar and the ignition switch is in the OFF/LOCK or KEY-OUT position.
• 10 minutes have elapsed since the ignition switch was changed from ACC or RUN to the OFF/LOCK position.

Inspection and Verification

1. Verify the customer concern by operating the system.

1. Visually inspect for obvious signs of mechanical or electrical damage.
   
   

   Visual Inspection Chart
   Mechanical Electrical

   • Window regulator motor
   • Window glass
   • Central junction box (CJB) Fuse:
     • 6 (5A)
     • 8 (5A)
     • 15 (5A)
     • 17 (10A)
     • 18 (5A)
     • 20 (5A)
   • Battery junction box (BJB) Fuse:
     • 103 (50A)
     • 110 (30A)
     • 116 (40A)
     • 601 (30A)
   • Relay(s)
   • CJB
   • BJB
   • Window control switch
   • Window regulator motor
   • GEM
   • Circuitry
   • Damaged wiring harness
   • Loose or corroded connector(s)
   
   

1. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

1. If the scan tool does not power up:
   • check that the program card is correctly installed.
   • check the connections to the vehicle.
   • check the ignition switch is in RUN position.
   • If the scan tool still does not power up, refer to the scan tool manual.

1. Carry out the DATA LINK DIAGNOSTICS test. If the scan tool responds with:
   • CKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418-00.
   • NO RESP/NOT EQUIP for GEM, GO to Pinpoint Test A.
   • SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs, and carry out the self-test diagnostics for the GEM.

1. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.

1. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.

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• The one-touch down feature is inoperative

• Circuitry.
• Battery saver relay.
• One-touch down relay.
• Driver window control switch.
• Driver window regulator motor.
• Central junction box (CJB).
• Generic electronic module (GEM).

• GO to Pinpoint Test D.

push the door switches in by hand and see if the lights go out. Here's some diagnostic info:

Vehicles may be equipped with either a generic electronic module (GEM) or a central timer module (CTM) depending on vehicle options.

• Vehicles with 4-wheel drive or the power group option will be equipped with a GEM.
• Vehicles with 2-wheel drive and no power group option will be equipped with a CTM.

Courtesy Lamps The GEM and the CTM illuminate the interior lamps when any door is open or ajar. The interior lamps are: the interior lamp, the cargo lamp and the door courtesy lamp. The courtesy lamps will shut off when:

• The doors are closed and the illuminated entry (GEM only) feature is not active.
• The vehicle speed is greater than 15 mph (24 km/h). The interior lamps will not be reactivated until the vehicle speed is less than 10 mph (16 km/h) and a new door open warning lamp switch signal is received (GEM only).

The system inputs to the GEM/CTM are as follows:

• The door open warning lamp switches. (Grounded when door is ajar; an open circuit when the door is closed.)
• The vehicle speed sensor (VSS) input. (Sinusoid Wave: 0.7V-20V, 2.2 Hz/MPH [1.37 Hz/km/h] [GEM only].)

The system output to the GEM/CTM is as follows:

• The interior lamp relay coil output. (Grounded when activated; open circuit when deactivated.)

Interior Lamp Relay The GEM and the CTM control the interior lamps and illuminated entry function with the interior lamp relay.
The relay is activated by applying ground to the relay coil through GEM C267-15, and is deactivated by removing the ground signal.
Panel Dimmer Switch The panel dimmer switch is integrated into the headlamp switch and controls the interior lamps by activating the interior lamp relay.
Illuminated Entry (GEM Only) The GEM illuminates the interior lamps when an unlock signal is received from the remote anti-theft personality (RAP) module. The illuminated entry feature will be canceled when any of the following conditions are met:

• 25 seconds have elapsed since the illuminated entry feature was activated and the courtesy lamp feature is not activated.
• The GEM receives a request from the RAP module (remote transmitter lock button pressed) and the courtesy lamp feature is not activated.
• The ignition is in the RUN or START position and the courtesy lamp feature is not activated.

The illuminated entry inputs are:

• RAP illuminated entry request. (Grounded pulse of varying length.)
• Ignition switch in the RUN position. (Battery voltage on both the RUN and RUN/ACC inputs.)

The illuminated entry outputs are:

• Interior lamp relay coil output. (Grounded when activated; an open circuit when deactivated.)

RAP Module The RAP module sends a signal to the GEM on the illuminated entry request circuit to indicate a request to turn the illuminated entry feature on or off. Circuit 1013 (BR/LG) is normally sent 12 volts by the GEM. The RAP module shorts this circuit to ground with a pulse of either of the following lengths:

• 200 ms pulse from RAP receiver assembly requests illuminated entry ON (unlock button pressed).
• 300 ms pulse from RAP receiver assembly requests illuminated entry OFF (lock button pressed).

GEM Sleep Mode The GEM and the CTM sleep mode deactivate all outputs to conserve battery power. Sleep mode is entered when the ignition has not entered the RUN or ACC position and 45 minutes has elapsed since the last wake-up input was received. In this mode, GEM current consumption is reduced to 5.0 mA or less. During sleep mode the GEM monitors the following wake-up inputs:

• Both front door open warning lamp switches.
• Ignition switch in the key-in, ACC and RUN position.
• RAP illuminated entry request.

The GEM sleep mode outputs are:

• None. (All circuits are deactivated during sleep mode.)

If a change in any of the above inputs occur while the GEM is asleep, the GEM will wake up and monitor all of its inputs and have the ability to activate any of its outputs.
The following components are under the control of the battery saver relay:

• Interior lamp.
• Engine compartment lamp.
• Glove compartment lamp.
• Panel dimmer switch.
• Interior lamp relay.

The battery saver relay becomes active (relay coil is energized) when the GEM is in the awake mode, and is deactivated (relay coil is de-energized) in the sleep mode. The battery saver will remain active until the ignition switch is removed from the ACC or RUN position and 45 minutes have passed since the last active input was received (see sleep mode inputs). At that time, the relay will be deactivated and power to the above circuits will terminate.
The battery saver inputs are the GEM sleep mode inputs.
The battery saver output is the battery saver relay.
Inspection and Verification — GEM/CTM

1. The interior lighting system is a generic electronic module (GEM)/central timer module (CTM) controlled system. Refer to Section 419-10 for additional information regarding GEM/CTM diagnostic strategies.

1. Verify the customer concern by operating the interior lamps.

1. Visually inspect for obvious signs of mechanical and electrical damage.

Visual Inspection Chart Mechanical Electrical

• Switch(es)

• Fuse(s) 14 (15A), 15 (5A), 4 (5A), 8(5A), and 103 (50A).
• Wiring harness
• Loose or corroded connector(s)
• Circuitry open/shorted
• Bulb(s)

1. If the concern remains after the inspection, connect the New Generation STAR (NGS) Tester to the data link connector (DLC) located beneath the instrument panel, and select the vehicle to be tested from the NGS menu. If the NGS does not communicate with the vehicle:
   • check that the program card is correctly installed.
   • check the connections to the vehicle.
   • check the ignition switch position.

I think you have a bad GEM Generic Electronic Module. get from car-part.com page with asterisk is lowest price



The GEM constantly monitors the system and reports concerns in the form of diagnostic trouble codes (DTCs). The DTCs can be retrieved with the Rotunda New Generation Star (NGS) Tester 007-00500 or equivalent through the communication link. The NGS is a menu-driven tester, allowing the user to run specific diagnostic tests. The NGS can isolate faults in the GEM subsystems through a symptom-driven diagnostic procedure. Connecting the tester to the GEM communication link will NOT alert the GEM. If the GEM is "asleep" when the diagnostic connector is plugged in, the GEM must be "awakened." If the communication link cannot be established, it is advised to turn the ignition to RUN. NOTE: The GEM has a sleep function to minimize battery consumption. During the sleep mode, the GEM turns off all outputs and monitors only the following:

• Door ajar (driver's door, passenger's door, liftgate, rear right and rear left doors)
• Key in ignition
• Key in RUN or ACCY
• Door handles (driver's or passenger's)
• Two-step unlock switch
• Neutral safety switch
• Illuminated entry request — RAP module

If a change of status occurs at one of these inputs while the GEM is asleep, the GEM will "wake up." When the GEM awakens, it performs an internal self test, and begins normal operation. At this point, the GEM will have all of its functions operational. The GEM will go into the sleep mode immediately after both of the following conditions have been met:

• Key in OFF or key not in ignition
• After 45 minutes with no change on any wake-up input

The GEM control system has two modes of operation, the normal operating mode and tester dependent diagnostics mode. The normal operation of the GEM can detect errors. An integral part of the normal GEM operation is the continuous diagnostics capability. Continuous diagnostics detects errors and changes the GEM control strategy. There is no warning light for the GEM; therefore, a DTC concern will direct you to the GEM. Examples of faults that may be detected during normal operation include:

• GEM continuous self test (RAM, ROM, EEPROM, A/D checking)
• Output driver monitoring (open circuit/short to GND, short to battery) NOTE: The GEM can only detect open circuit/short to GND faults when the GEM is not energizing a load, and short to battery faults when the GEM is attempting to energize a load.
  
• Illogical combinations of input signals

A description of the subsystems controlled by the GEM follows.

Courtesy Lamps
The GEM illuminates the interior courtesy lamps when any door is set ajar or is opened. The following are inputs used for controlling the courtesy lamps:

• All door ajar switches (including liftgate)
• Door handle switches
• Illuminated entry request with RAP module
• Two-step unlock door disarm switches.

All interior courtesy lamps are turned off when any of the following occurs:

• 25 seconds have elapsed after all the doors are closed.
• The ignition switch is turned to RUN.
• Vehicle speed is over 8 km/h (5 mph).
• A power door lock command is received before the five seconds have elapsed.

One-Touch Window
When the power switch for driver's window control is held down (between 0.04 and 0.4 second) and then released with the ignition switch in RUN or ACC, the driver's window will automatically move to its full down position. Only the driver's window has this feature. Holding the driver's switch down longer allows the operator to stop the window as soon as the switch is released. The one-touch window feature can be enabled or disabled by the operator.

1. Close both front doors .

1. Key ON.

1. Key OFF.

1. Remove key from ignition switch .

1. Press and hold the down window switch to enable/disable the one-touch window feature.

1. Reinsert the key into the ignition switch within two seconds after pressing the down window switch.

1. Continue to hold the switch until a two-second tone is heard.

1. Release the switch while the tone is active.

1. After the two-second tone, the following confirmation beep sequences will be heard:
   • One beep — feature disabled.
   • Two beeps — feature enabled.
   Repeat the procedure again to toggle back and forth.
   

Generic Electronic Control Module (GEM), Central Timer Module (CTM) Removal and Installation

1. Disconnect battery ground cable (14301) .

1. Remove radio, refer to Section 15-01 .

1. Remove radio bezel.

1. Remove retaining screw.

1. Slide GEM/CTM toward front of vehicle, off retaining tabs.

1. Disconnect electrical connectors.
   
   
   
   NOTE: When the battery (10655) has been disconnected and reconnected, some abnormal drive symptoms may occur while the powertrain control module (PCM) (12A650) relearns its adaptive strategy. The vehicle may need to be driven 16 km (10 miles) or more to relearn the strategy.
   For installation, follow removal procedures in reverse order. Tighten retaining screw to 2.3-3.3 Nm (20.4-29.2 lb-in). NOTE: The automatic ride control switch must be turned to the OFF position when the vehicle is hoisted, jacked, towed, jump-started or raised off the ground to avoid unnecessary operation of the system and/or possible damage to its components.
   

I would suspect you have a bad door switch on one of the doors or liftgate. They are usually plunger switches. Try pusing them in one at a time and see f the lights go out. Hold it in long enough to account for the time delay.

please rate if this helps you.

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• The Courtesy Lamps Stay On Continuously

• Circuitry.
• GEM/CTM.
• Ignition switch.
• Interior lamp relay.
• Dimmer module.
• Door ajar switch.
• DTC B1322.
• DTC B1330.
• DTC B1334.
• DTC B1338.
• DTC B1371.
• DTC B1574.
• DTC B1610.

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Generic Electronic Module (GEM)/Central Timer Module (CTM) Controlled Functions
The generic electronic module (GEM) is equipped on four-wheel drive vehicles with power windows. The central timer module (CTM) is equipped only on two-wheel drive vehicles without power windows.
NOTE: GEM/CTM diagnostics are compatible with New Generation STAR (NGS) Tester.
The GEM/CTM incorporates the functions of several different modules into one, and offers diagnostics to easily locate and repair concerns affecting the subsystems that it controls.
The GEM/CTM constantly monitors the systems under its control and reports a concern in the form of a diagnostic trouble code (DTC). A DTC can be retrieved with NGS Tester through the communication link.
NGS Tester is a menu-driven tester that allows the user to run specific tests. NGS Tester can isolate faults in the GEM/CTM subsystems through a symptom-driven diagnostic procedure. Connecting NGS Tester to the GEM/CTM communication link will not alert the GEM/CTM. If the GEM/CTM is "asleep" when the diagnostic connector is plugged in, the GEM/CTM must be "awakened". If the communication link cannot be established, it is advised to turn the ignition to RUN.
NOTE: The GEM/CTM has a sleep function to minimize battery consumption. During the sleep mode, the GEM/CTM turns off all outputs and monitors only the following:

• Door ajar (driver door, passenger door, liftgate, LH rear and RH rear doors).
• Key-in-ignition.
• Key in RUN or ACC.
• Two-step unlock switch (unarm switch).
• Digital TR sensor.
• Illuminated entry request (remote anti-theft personality [RAP] module).

If a change of status occurs at one of these inputs while the GEM/CTM is asleep, the GEM/CTM will "wake up." When the GEM/CTM awakens, it performs an internal self-test, and begins normal operation. At this point, the GEM/CTM will have all of its functions operational.
The GEM/CTM will go into the sleep mode immediately after both of the following conditions have been met:

• Key in OFF or key not in ignition.
• After 45 minutes with no change in any wake-up input.

The GEM/CTM control system has two modes of operation; the normal operating mode and the tester-dependent diagnostics mode.
The normal operation of the GEM/CTM can detect errors. An integral part of the normal GEM/CTM operation is the continuous diagnostic capability. Continuous diagnostics detects errors and changes the GEM/CTM control strategy. There is no warning lamp for the GEM/CTM; therefore, a DTC concern will direct you to the GEM/CTM. Examples of faults that may be detected during normal operation include:
NOTE: The GEM/CTM can only detect open circuit/short to GRD faults when the GEM/CTM in not energizing a load, and short to battery faults when the GEM/CTM is attempting to energize a load.

• GEM/CTM continuous self-test (RAM, ROM, EEPROM, A/D checking).
• Output driver monitoring (open circuit/short to ground [GRD], short to power).

• Illogical combinations of input signals.

you need to have your GEM module reconfigured after battery disconnect. It controls many functions. It may have also been damaged during battery change due to a voltage spike. Dealer can test it. Call a dealer service dept and describe symptoms and see what they say.

Module Controlled Functions NOTE: Prior to removal of the generic electronic module (GEM), it is necessary to upload module configuration information to the scan tool. This information needs to be downloaded into the new module once installed. For additional information, refer to Section 418-01 .
NOTE: Electronic modules are sensitive to electrical charges. If exposed to these charges, damages may result.
The generic electronic module (GEM) is the only multi-function module on this vehicle.
The GEM constantly monitors its subsystems for concerns. If a concern is found in one of the subsystems, the GEM will record the concern in the form of a diagnostic trouble code (DTC).
The ignition switch position is very important to the GEM functionality Erratic or unexpected GEM functions can often be traced to problems with these GEM inputs.
The GEM controls a variety of systems:

• instrument cluster warning indication and chimes
• interior courtesy lamp control
• automatic headlamp control
• daytime running lamps (DRL)
• wiper and washer (front only)
• heated rear window
• one-touch down power window
• delayed accessory
• power door locks (including SMART, autolocking and luggage compartment lid release)
• remote keyless entry
• perimeter anti-theft

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Principles of Operation
The generic electronic module (GEM) constantly monitors its subsystems for concerns. If a concern is found in one of the subsystems, the GEM will record the concern in the form of a diagnostic trouble code (DTC).
The ignition switch position is very important to the GEM functionality. Erratic or unexpected GEM functions can often be traced to problems with these GEM inputs.
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