1998 jimmy 4 wheel drive problem

What large square fuse ? The 4X4 switch get's it's B+ voltage from the four - wheel drive control module . computer controlled ! Has two relay's - transfercase hi to low & low to high ,located in the Auxiliary relay box #3 . location left side of radiator core support . Your best bet ,take it to a qualified repair shop that has a diagnostic tool that can communicate with the 4X4 control module . Read code's ! Probably has a code like one of these
P1812 Transmission 4-Wheel Drive Mode Select Circuit Failure 4WD control module Go To Pinpoint Test D . P1815 Transmission 4-Wheel Drive Mode Select Short Circuit to Ground 4WD control module Go To Pinpoint Test A .
But code have a few others as well .
B2105 Throttle Position Input Out of Range Low 4WD control module Go To Pinpoint Test B . B2106 Throttle Position Input Out of Range High 4WD control module Go To Pinpoint Test B . C1728 Transfer Case Unable to Transition Between 2H and 4H. 4WD control module Go To Pinpoint Test C . C1729 Transfer Case Unable to Transition Between 4WD HIGH and 4WD LOW 4WD control module Go To Pinpoint Test D . C1979 IWE Solenoid Circuit Failure 4WD control module Go To Pinpoint Test F . C1980 IWE Solenoid Short to Battery 4WD control module Go To Pinpoint Test F . P1812 Transmission 4-Wheel Drive Mode Select Circuit Failure 4WD control module Go To Pinpoint Test D . P1815 Transmission 4-Wheel Drive Mode Select Short Circuit to Ground 4WD control module Go To Pinpoint Test A . P1824 Transmission 4-Wheel Drive Clutch Relay Circuit Failure 4WD control module Go To Pinpoint Test A . P1826 Transmission 4-Wheel Drive Low Clutch Relay Short Circuit to Battery 4WD control module Go To Pinpoint Test A . P1827 Transmission 4-Wheel Drive Low Clutch Relay Short Circuit to Ground 4WD control module Go To Pinpoint Test A . P1849 Transmission Transfer Case Contact Plate A Short Circuit to Ground 4WD control module Go To Pinpoint Test D . P1853 Transmission Transfer Case Contact Plate B Short Circuit to Ground 4WD control module Go To Pinpoint Test D . P1857 Transmission Transfer Case Contact Plate C Short Circuit to Ground 4WD control module Go To Pinpoint Test D . P1861 Transmission Transfer Case Contact Plate D Short Circuit to Ground 4WD control module Go To Pinpoint Test D . P1867 Transmission Transfer Case Contact Plate General Circuit Failure 4WD control module Go To Pinpoint Test D . P1891 Transmission Transfer Case Contact Plate Ground Return Open Circuit 4WD control module Go To Pinpoint Test D .

4X4

On these issue, there are few solved help links for troubleshooting the issue easily.-------

Click the link below: ---

No 4x4 light on dash?

http://repairhelpcenter.blogspot.com/2011/12/no-4x4-light-on-dash.html

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4X4 Truck makes roaring noise in the front end?

http://schematicsdiagram.blogspot.com/2012/01/4x4-truck-makes-roaring-noise-in-front.html

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Car will not go into 4WD high or 4WD low?

http://schematicsdiagram.blogspot.com/2011/12/car-will-not-go-into-4wd-high-or-4wd.html

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No 4x4 light on dash?

http://repairhelpcenter.blogspot.com/2011/12/no-4x4-light-on-dash.html

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4 wheel drive system will not disengage?

http://technoanswers.blogspot.com/2012/01/4-wheel-drive-system-will-not-disengage.html

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4WD light is flashing and beeping? NO 4WD high?

http://schematicsdiagram.blogspot.in/2012/02/4wd-light-is-flashing-and-beeping-no.html

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2002 Jeep Wrangler: 4WD Idiot Light is ON?

http://technoanswers.blogspot.in/2012/06/2002-jeep-wrangler-4wd-idiot-light-is.html

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Traction control switch will not engage on 4WD High or Low

http://whoisbyme.blogspot.com/2012/10/traction-control-switch-will-not-engage.html

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4WD light flashing and 4WD will engage after few minutes

http://repairhelpcenter.blogspot.com/2012/10/4wd-light-flashing-and-4wd-will-engage.html

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2008 Toyota Tundra: 4x4 Wheel Drive Light is Flashing?

http://technoanswers.blogspot.in/2012/05/2008-toyota-tundra-4x4-wheel-drive.html

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4x4 front differential will not engage the axle on ford?

http://technoanswers.blogspot.in/2012/02/4x4-front-differential-will-not-engage.html

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4x4 will not engage on Ford F150?

http://technoanswers.blogspot.in/2012/02/4x4-will-not-engage-on-ford-f150.html

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Dodge Ram 4x4 light keeps flashing

4X4 LOW LIGHT IS FLASHING ON DASH

http://technoanswers.blogspot.in/2012/09/dodge-ram-4x4-light-keeps-flashing.html

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Ford 4x4 front wheels will not engage?

http://technoanswers.blogspot.in/2012/02/ford-4x4-front-wheels-will-not-engage.html

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These details will help.

Thanks.

there is a transfere case shift control module . (think it is under the passager side dash kick pannel ) this module recives a signal from the 4wd switch that tells it to shift the transferecase into 4wheel, there is also a motor on the trasferecase too . Now its hard to test these with out a scan tool because you need to see if each component is sending and recievcing the proper comand .

if its electric shift. its probly the shifter motor. start vehicle open the door listen 4 the shifter motor. 2 see if you can hear it trying 2 shift. if not thats what it is if you can hear it tryng 2 shift it mite be vacume lines

3 button or 4 button. If 3 button remove the pass side kick panal and diconnect the module you see there with the key on. 3 or 4 button the trucks are known for water leaks and they fill the module(3 or 4 button module are in the same place) causing all kinds of problems. What has happened to my jimmy same year was the front diff actuator ( under the battery tray) was full of transmission oil. I worked at a gm dealer as a trans tech. The front diff actuator had blown a hole in it. I have to replaced the 4wd vac switch on top of the transfer case that was where I got the oil from, also the actuator and the vacume ball behind the abs motor pack as it to was full of oil. if lucky you will not have to change your hvac control head.

check fuse and relay to switch if power to switch retest switch new doesnt mean not defective if no power check connections and wiring for damage or breaks

Pull the kick panel on the passenger side. there is a small box mounted there that is the computer that controls the actuator for the 4wd system. this is notorious for problems due in fact that the connector likes to pull out and away from the module. I had the same problem and the solution is simple.. take a long zip tie and get it between a few of the wires and around the module. tie it in and have a nice day.. it wont come off or try to pop out anymore and you should have no issues getting into 2wd, 4wd h, 4wd L.

sounds like the hubs arent locking. try that or there is a modual under your drivers seat or in drivers kick panel could be coulprit

2-Speed Torque-On-Demand (TOD) Operation
The automatic 4-wheel drive (A4WD) system is a 2-speed torque-on-demand (TOD) operation that utilizes the following components:

• Transfer case
• 4-wheel drive (4WD) control module (integral to the powertrain control module [PCM])
• Mode select switch (MSS)
• Gearmotor encoder assembly (part of the transfer case shift motor)
• Transfer case shift motor
• Shift motor sense plate (part of the gearmotor encoder assembly)

Principles of Operation
Transfer Case Shift Motor The externally mounted transfer case shift motor, located at the rear of the transfer case, turns the shift cam assembly. As the shift cam assembly turns, it positions the reduction shift fork for desired transfer case operation. An integral position sensor in the shift motor provides shift motor position information to the 4WD control module.
Mode Select Switch (MSS) The push button MSS, mounted on the instrument panel, allows the operator to select the 4x4 Auto, 4x4 High, and 4x4 Low transfer case operating modes. The indicator light, on the instrument cluster push button, will illuminate only when the 4x4 Low position is engaged.
Visual Inspection Chart Mechanical Electrical

• Axle shafts and CV joints
• Driveshaft and universal joints
• Fluid leaks
• Matching tire sizes
• Transfer case shift motor

• Battery junction box (BJB) fuses:
  • 8 (30A)
  • 17 (5A)
  • 18 (20A)
• Central junction box (CJB) fuses:
  • 12 (5A)
  • 24 (15A)
• 4x4 module (PCM)
• Wiring harness
• Gearmotor encoder contact plate
• Connector(s)
• Circuitry
• Mode indication switch (MSS)

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 concern is not visually evident, connect the diagnostic tool to the data link connector and select the vehicle to be tested from the diagnostic tool menu. If the diagnostic tool 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.

1. If the diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool operating manual.

1. Carry out the diagnostic tool data link test. If the diagnostic tool responds with:
   • CAN circuit fault; all electronic control units no response/not equipped, refer to Section 418-00 .
   • No response/not equipped for 4WD module (PCM), Go To Pinpoint Test G .
   • System passed, retrieve and record the continuous diagnostic trouble codes (DTCs), erase the continuous DTCs and carry out the 4WD module (PCM) self test.

1. If the DTCs retrieved are related to the concern, go to the 4WD Control Module (PCM) Diagnostic Trouble Code (DTC) Index to continue diagnostics. 4WD Control Module (PCM) Diagnostic Trouble Code (DTC) Index
   DTC Description Source Action B1317 Battery Voltage HIGH 4WD Module (PCM) REFER to Section 414-00 . B1318 Battery Voltage LOW 4WD Module (PCM) REFER to Section 414-00 . B1319 Driver Door Ajar Circuit Failure 4WD Module (PCM) Go To Pinpoint Test M . B1322 Driver Door Ajar Circuit Short To Ground 4WD Module (PCM) Go To Pinpoint Test M . B1342 ECU is Defective 4WD Module (PCM) CLEAR the DTCs. REPEAT the 4x4 module (PCM) self test. If DTC B1342 is retrieved, INSTALL a new 4x4 module (PCM). REFER to Section 303-14 . CLEAR the DTCs. REPEAT the self test. B1483 Brake Pedal Input Circuit Failure 4WD Module (PCM) Go To Pinpoint Test M . B1485 Brake Pedal Input Short to Battery 4WD Module (PCM) Go To Pinpoint Test M . C1729 Transfer Case Unable to Transition Between 4H and 4L 4WD Module (PCM) Go To Pinpoint Test K . C1970 4WD Low Mode Switch LED Short to Battery 4WD Module (PCM) Go To Pinpoint Test K . C1971 4WD Low Mode Switch LED Circuit Failure 4WD Module (PCM) Go To Pinpoint Test K . P1707 Transfer Case NEUTRAL or PARK/NEUTRAL Indication Circuit 4WD Module (PCM) Go To Pinpoint Test M . P1812 Transmission 4-Wheel Drive Mode Select Circuit Failure 4WD Module (PCM) Go To Pinpoint Test K . P1815 Transmission 4-Wheel Drive Mode Select Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test K . P1816 Transmission NEUTRAL Safety Switch Circuit Failure 4WD Module (PCM) Go To Pinpoint Test M . P1819 Transmission NEUTRAL Safety Switch Circuit Short to Ground 4WD Module (PCM) Go To Pinpoint Test M . P1820 Transfer Case Clockwise Shift Relay Coil Circuit Failure 4WD Module (PCM) Go To Pinpoint Test K . P1822 Transfer Case Clockwise Shift Relay Coil Circuit Short To Battery 4WD Module (PCM) Go To Pinpoint Test K . P1824 4-Wheel Drive Clutch Relay Circuit Failure 4WD Module (PCM) Go To Pinpoint Test H . P1826 4-Wheel Drive Low Clutch Relay Short Circuit to Battery 4WD Module (PCM) Go To Pinpoint Test H . P1827 4-Wheel Drive Low Clutch Relay Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test H . P1828 Transfer Case Counterclockwise Shift Relay Coil Circuit Failure 4WD Module (PCM) Go To Pinpoint Test K . P1830 Transfer Case Counterclockwise Shift Relay Coil Circuit Short To Battery 4WD Module (PCM) Go To Pinpoint Test K . P1849 Transfer Case Contact Plate A Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test K . P1853 Transfer Case Contact Plate B Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test K . P1857 Transfer Case Contact Plate C Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test K . P1861 Transfer Case Contact Plate D Short Circuit to Ground 4WD Module (PCM) Go To Pinpoint Test K . P1867 Transfer Case Contact Plate General Circuit Failure 4WD Module (PCM) Go To Pinpoint Test K . P1891 Transfer Case Contact Plate Ground Return Open Circuit 4WD Module (PCM) Go To Pinpoint Test K . U1900 CAN Communication BUS Fault 4WD Module (PCM) REFER to Section 418-00 . U2023 External Node Fault 4WD Module (PCM) REFER to Section 418-00 . U2051 One Or More Calibration Files Missing/Corrupt 4WD Module (PCM) Reprogram/Reflash the 4x4 module. REFER to Section 418-00 . - For All Other DTCs 4WD Module (PCM) REFER to Section 418-00 .
2. Your best bet mite be to take it to a qualified repair shop !

the module is what i would suspect. and i do believe it is in the r kick panel. i've seen the button pack on dash go bad too, but module is best bet.