Replacement cost estimate for C Class Transmission Control Module

Chevrolet Tahoe Powertrain Control Module Replacement Cost

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The average cost for a Chevrolet Tahoe powertrain control module replacement is between $448 and $514. Labor costs are estimated between $96 and $121 while ..

Question edited for full make and model.
Check moved to sub category.

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7 Symptoms of a Bad Transmission Control Module

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Repair Cost - Need immediate help for your car problem? Chat online with an expert: A car's TCM will likely never need replacing, but if you have a bad ...
‎Signs of a Bad Transmission... · ‎- Check Engine Light · ‎- Stuck in the Same Gear

Signs of a Bad Transmission Control Module & TCM ...

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Oct 28, 2019 - Signs of a bad transmission controle module you should know, the cost to replace the TCM, and variables to consider.

6 Symptoms Of A Bad Transmission Control Module (TCM)

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Transmission Control Module Replacement Cost - The most common symptom of a bad TCM is a check engine light or a transmission fault warning light on your ...
‎Bad Transmission Control... · ‎No Gear shifting at all

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DTC P1780
Circuit Description
This DTC indicates that the engine control module (ECM) received a message from the transmission control module (TCM) to turn ON the MIL (SERVICE ENGINE SOON) telltale due to a transmission related OBD II failure. The ECM will send a message via the controller area network (CAN) link to the body control module (BCM), which will send a message over the class 2 link to the instrument panel (I/P) cluster to turn ON the MIL.
Conditions for Setting the DTC
DTC P1780 will set if the ECM received a MIL request message from the TCM over the CAN link.
DTC P1780 is a type B DTC.
Diagnostic Aids
DTC P1780 does not indicate a fault with the CAN link circuit.
DTC P1780 does not indicate a fault with the ECM.
Diagnose any TCM related DTCs first.


You need a scan tool that can read transmission control module codes .

Transmission control module is part of the PCM - powertrain control module . Engine an transmission module all in one . It's in the engine compartment .
Powertrain Control Module (PCM) 4.8L,5.3L,6.0L
Near the left front inside the engine compartment

You probably have a problem with

Automatic Transmission Shift Lock Control System
The automatic transmission shift lock control system is a safety device that prevents an inadvertent shift out of PARK when the engine is running. The driver must press the brake pedal before moving the shift lever out of the PARK position. The system consists of the following components.
• The automatic transmission shift lock control solenoid
• The brake switch
• The rear integration module (RIM)
• The transmission control module (TCM) or powertrain control module (PCM)
With the ignition ON, battery positive voltage is supplied to the automatic transmission shift lock control solenoid from the ignition 3 relay. The automatic transmission shift lock control solenoid is controlled by the rear integration module. When the rear integration module (RIM) receives a class 2 serial data message from the transmission control module (TCM) or powertrain control module (PCM) indicating that the shift lever is in the PARK position the rear integration module (RIM) grounds the automatic transmission shift lock control solenoid control circuit. This causes the solenoid to energize mechanically locking the shift lever in the PARK position. When the driver presses the brake pedal the rear integration module receives the brake applied signal and turns off the ground to the automatic transmission shift lock control solenoid control circuit. This allows the shift lever to be moved out of the PARK position.

Shift Lever Does Not Move with Brake Pedal Depressed

2
Apply the parking brake and block the wheels.
Turn ON the ignition, with the engine OFF.
Attempt to move the shift lever out of the PARK position.
Does the shift lever move out of the PARK position?
YES - Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
NO - Go to Step 3
3
Turn OFF the ignition.
Install a scan tool.
Turn ON the ignition, with the engine OFF.
With a scan tool, observe the TCC brake switch parameter in the transmission data display list.
Press and release the brake pedal several times.
Does the TCC brake switch status turn ON and OFF with the brake pedal?
YES - Go to Step 4
NO - Go to Stop Lamps Inoperative in Lighting Systems
4
With a scan tool, observe the brake to shift control parameter in the rear integration module data list.
Press and release the brake pedal several times.
Does the brake to shift control status turn ON and OFF with the brake pedal?
YES - Go to Step 5
NO - Go to Step 8
5
Turn OFF the ignition.
Connect a test lamp between the automatic transmission shift lock control solenoid supply voltage circuit and the automatic transmission shift lock control solenoid control circuit at the automatic transmission shift lock control solenoid.
Turn ON the ignition, with the engine OFF.
With a scan tool, command the brake to shift control ON and OFF several times while observing the test lamp.
Does the test lamp turn ON and OFF with each command?
YES - Go to Step 7
NO - Go to Step 6
6
Test the automatic transmission shift lock control solenoid control circuit for and open or short to battery voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
YES - Go to Step 11
NO - Go to Step 8
7
Inspect for poor connection at the harness connector of the automatic transmission shift lock control solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
YES - Go to Step 11
NO - Go to Step 9
8
Inspect for poor connections at the harness connector of the rear integration module (RIM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Yes - Go to Step 11
NO - Go to Step 10
9
Replace the automatic transmission shift lock control solenoid. Refer to Automatic Transmission Shift Lock Actuator Replacement .
YES - Did you complete the replacement?
NO - Go to Step 11
--
10
Replace the RIM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
YES - Did you complete the replacement?
NO - Go to Step 11
--
11
Operate the system in order to verify the repair.
Did you find and correct the condition?
YES - System OK
NO - Go to Step 2

it is integral to the transmission , i've put a link to a video , shows the basic procedure so you will know if it's something you could do or get a mechanic
Mercedes Benz Transmission Control Module Replacement

You just don't throw a part on, If the problem is the transmission range selector switch (not the control module) the cost to repair will be around $250.00
P0706 AUDI - Transmission Range Sensor Circuit Range Performance
Possible causes- Open or short park/neutral position switch circuit
- Poor park/neutral position switch circuit connection
- Misadjusted park/neutral position switch
- Park/neutral position switch may be faulty
When is the code detected?The transmission range switch detects the selector lever position and sends a signal to the TCM.

Check under seat unplug control module see if it is wet with fluid . cost me $138.00 fee.
Engine light on than next day off may 2 day then on at same place drive kid to school.
issue with transmission fluid wicking up the harness into the control module and causing the module to malfunction. Usually, the harness from the transmission to the ETC module is replaced and the module is replaced provided the leak is repaired. In some cases this may be more than is actually needed but it usually fixes the concern. Transmission fluid does not actually damage the module and can be flushed away with board cleaning solvent or electrical contact cleaner as a first attempt. Always repair the leak before replacing a module.
http://www.benzworld.org/forums/w163-m-class/1465231-mercedes-repair-maintainance-transmission-etc-tips.html

Before condemning the transmission, I would check the shift cable for proper operation. Look at the side of the transmission where the shift cable attaches. Have someone shift the transmission from PARK to FIRST. The engine should not be running. If the operating lever on the transmission moves, then you probably do have an internal transmission problem.
If the operating lever does not move, you have a broken shift cable or it has popped of it's attachments at the operating lever or gear shift handle.

A bad Transmission Control Module (TCM) would not keep it from shifting. In the event of a bad TCM, the transmission would go into fail safe mode and you could continue driving the vehicle.

Hello,
I also was concerned about my tranny in my 1998 dodge caravan. I replaced the fluid & filter and it worked for a while. I finally had to bring it to AAMCO Transmission and they gave me a free evaluation of it & an estimate for the job. I had the option of ignoring their evaluation results and bring it home or just bite the bullet and have it repaired. I thought I could get a lot more miles out of it so I had it fixed for $1400 with no regrets.

Perhaps if you can find a similar place with free evaluation & estimate then that would be the thing to do as you seemed to have covered all the other bases.

Good Luck!
Rich Lilja