Diagnostic Test
- 1) CHECK IF SPEED SENSOR DTCS ARE PRESENT
With the scan tool, read Transmission DTCs.
Are there any speed sensor DTCs present also?
Yes
- Perform appropriate DTC test(s) in this article.
No
- Go To step 2).
- 2) CHECK IF SHIFT LEVER ASSEMBLY SHIFT CABLE IS OUT OF ADJUSTMENT
Check the Shift Lever Assembly shift cable for proper adjustment. Refer to AUTOMATIC TRANSMISSION-AUTOMATIC TRANSMISSION NAG1/SERVICE INFORMATION for the proper service procedures.
Is the Shift Lever Assembly shift cable properly adjusted?
Yes
- Go To step 3).
No
- Adjust the Shift Lever Assembly shift cable per the Service Information. (Refer to TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/GEAR SHIFT CABLE - ADJUSTMENTS)
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
- 3) CHECK IF ENGINE STARTS IN PART OR NEUTRAL
Attempt to start the engine in Park or Neutral.
Does the engine start in either Park or Neutral?
Yes
- Go To step 4).
No
- Go To step 5).
- 4) TRANSMISSION TEMPERATURE SENSOR-P/N SWITCH
Turn the ignition off to the lock position.
Disconnect the TCM C2 harness connector.
Place the gear selector in Drive.
Measure the resistance of the Transmission Temperature Sensor between the (T54) Temperature Sensor-P/N Switch Signal circuit and the (T13) Sensor Ground circuit in the TCM C2 harness connector.
Is the resistance between 500 to 2500 ohms?
Yes
- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM per the Service Information. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - DESCRIPTION)
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
No
- Using the schematics as a guide, check the Electrohydraulic Control Unit Assembly and Transmission Temperature Sensor-P/N Switch pins and connector terminals for corrosion, damage, or terminal push out. If no problems are found, replace the Transmission Temperature Sensor-P/N Switch. (Refer to TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/ELECTROHYDRAULIC UNIT - DISASSEMBLY)
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
- 5) CHECK THE TRANSMISSION TEMPERATURE SENSOR-P/N SWITCH
Turn the ignition off to the lock position.
Reconnect the TCM C2 harness connector.
Disconnect the Electrohydraulic Control Unit Assembly harness connector.
NOTE: This procedure may set various DTCs to multiple modules connected to the CAN bus. Disregard and erase any DTCs that may set after completion of this procedure.With the Shift Lever in the Park position, attempt to start the engine.
Does the engine start?
Yes
- Replace the Transmission Temperature Sensor-P/N Switch. (Refer to TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/ELECTROHYDRAULIC UNIT - DISASSEMBLY)
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
No
- Go To step 6).
- 6) CHECK IF THE (T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT IS SHORTED TO GROUND
Courtesy of DAIMLERCHRYSLER CORP.
Turn the ignition off to the lock position.
Reconnect the Electrohydraulic Control Unit Assembly harness connector.
Disconnect the TCM C1 and C2 harness connectors.
Measure the resistance between ground and the (T54) Temperature Sensor-P/N Switch Signal circuit.
Is the resistance below 5.0 ohms?
Yes
- Repair the (T54) Temperature Sensor-P/N Switch Signal circuit for a short to ground.
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
No
- Go To step 7).
- 7) CHECK IF (T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT IS SHORTED TO ANOTHER CIRCUIT(S)
Courtesy of DAIMLERCHRYSLER CORP.
Measure the resistance between the (T54) Temperature Sensor-P/N Switch Signal circuit and all other circuits in the TCM C1 and C2 harness connectors.
Is the resistance below 5.0 ohms between the (T54) Temperature Sensor-P/N Switch Signal circuit and any other circuit(s)?
Yes
- Repair the (T54) Temperature Sensor-P/N Switch Signal circuit for a short to another circuit(s).
- Perform NAG1 TRANSMISSION VERIFICATION TEST .
No
- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the TCM per the Service Information. (Refer to ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE - DESCRIPTION)
- Perform NAG1 TRANSMISSION VERIFICATION TEST .