P0710-TRANSMISSION TEMPERATURE SENSOR CIRCUIT





For a complete wiring diagram Refer to Section 8W

Theory of Operation


The Electrohydraulic Control Unit Assembly of the NAG1 transmission contains a temperature sensor to monitor the transmission oil temperature. This sensor is wired in series with the transmission Park/Neutral switch. The Transmission Control Module (TCM) expects to see a valid voltage level from the sensor when the shifter is in Reverse or any forward Drive position. The TCM also expects to see an open circuit condition when the shifter is in the Park or Neutral position. When the controller detects an open circuit when in Reverse or any forward drive position the DTC will set. Note: Due to a open circuit condition in Park or Neutral, the TCM substitutes the Transmission Temperature reading with Engine Temperature when in Park or Neutral


  • When Monitored:

    Continuously with the ignition on.

  • Set Condition:

    When the TCM detects an open circuit when in Reverse or any forward drive position the DTC will set.


Possible Causes
  
SHIFT LEVER ASSEMBLY OUT OF ADJUSTMENT
  
(T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT OPEN
  
(T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT SHORT TO VOLTAGE
  
(T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT SHORT TO OTHER CIRCUITS
  
(T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT SHORT TO ANOTHER CIRCUIT(S)
  
SHIFT LEVER ASSEMBLY
  
TRANSMISSION CONTROL MODULE
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)



Diagnostic Test

1.CHECK IF SPEED SENSOR DTCS ARE PRESENT



Are there any speed sensor DTCs present also?

Yes
  • Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - DIAGNOSIS & TESTING and perform the appropriate symptom.


No
  • Go To 2

2.CHECK IF SHIFT LEVER ASSEMBLY SHIFT CABLE IS OUT OF ADJUSTMENT

(Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1/GEAR SHIFT CABLE - ADJUSTMENTS)

Is the Shift Lever Assembly shift cable properly adjusted?

Yes
  • Go To 3


No

3.CHECK IF ENGINE STARTS IN PARK OR NEUTRAL



Does the engine start in either Park or Neutral?

Yes
  • Go To 4


No
  • Go To 5

4.TRANSMISSION TEMPERATURE SENSOR-P/N SWITCH








Is the resistance between 500 to 2500 ohms?

Yes


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 per the Service Information.
  • Perform NAG1 TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)

5.CHECK THE TRANSMISSION TEMPERATURE SENSOR-P/N SWITCH




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.




Does the engine start?

Yes


No
  • Go To 6

6.CHECK IF THE (T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT IS SHORTED TO GROUND








Is the resistance below 5.0 ohms?

Yes


No
  • Go To 7

7.CHECK IF (T54) TEMPERATURE SENSOR-P/N SWITCH SIGNAL CIRCUIT IS SHORTED TO ANOTHER CIRCUIT(S)





Is the resistance below 5.0 ohms between the (T54) Temperature Sensor-P/N Switch Signal circuit and any other circuit(s)?

Yes


No
  • Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors 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 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/TRANSMISSION CONTROL MODULE for the appropriate service procedure.
  • Perform NAG1 TRANSMISSION VERIFICATION TEST. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - NAG1 - STANDARD PROCEDURE)