Transmission Temperature Sensor/Switch: Testing and Inspection

SSTs:

TRANSAXLE TESTER INSTRUCTION
The transaxle tester allows a technician to operate the electrical portion of the transaxle independent of the vehicle electronics. The transaxle tester usage is divided into five steps.
1. Preliminary testing and diagnosis.
2. Installing the transaxle tester.
3. Static testing-vehicle OFF.
4. Dynamic testing-vehicle running.
5. Removing the transaxle tester and clearing Diagnostic Trouble Codes (DTCs).

Preliminary Testing and Diagnosis
Before any diagnostic testing is done on a vehicle some preliminary checks must be performed, as outlined below. Be sure to write down your findings, especially any DTC, for future reference.
- Check ATF level and condition.
- Check for add-on items (phones, computers, CB radio etc).
- Visually inspect wiring harness and connectors.
- Check for vehicle modifications.
- Verify that the shift linkage is properly adjusted.
- Verify customer concern.
- Upshift, Downshift, Coasting, Engagement, Noise/Vibration
- Vehicle must be at normal operating temperature.
- Perform vehicle On-Board Diagnostic Test.
- Record all DTCs.
- Repair all non-transaxle DTCs.

Installing The Transaxle Tester (Set Up Procedures)
Installing the transaxle tester at the solenoid body connector allows the separation of the vehicle electronics from the transaxle electronics. Disconnecting the normal vehicle electronics will in itself set additional DTCs and cause firm shifts. (Disconnecting the solenoid body connector defaults the transaxle to maximum line pressure).

NOTE:
^ During tester usage additional DTCs may be set.
^ Therefore, it is important that all DTCs are erased after repairs have been made. To verify elimination of all DTCs, rerun the On-Board Diagnostic Test.

CAUTION: Do not attempt to pry off connectors with a screwdriver. This will damage the connector and could result in a transaxle concern.

1. Disconnect the emission harness at the solenoid body connector and at the TSS connector on the oil pump body in the LH wheel arch.




2. Turn the tester solenoid select switch to the "OHMS CHECK" position.




CAUTION: Route all cables away from heat sources.

3. Install the SST onto tester.
Connect the SST to the transaxle tester and then to the appropriate solenoid body connector and TSS connector.




CAUTION: Route all gauge lines away from heat sources.

4. Connect the SST to the line pressure inspection port.




5. Plug the transaxlee tester power supply plug into the cigarette lighter receptacle. At this time, all LED's should illuminate for a short period and then turn off. This is the tester internal circuit check.




6. Set the Bench/Drive switch to "BENCH" mode.

Static Testing-Vehicle "OFF"
Static testing procedures allow for shop testing of the transaxle in the vehicle or on the bench. Completion of these tests prove out the transaxle electronically.

Caution: For resistance checks, be sure that the tester solenoid select switch is set to the "OHMS CHECK" position or damage to the ohmmeter may result.

Resistance / Continuity Tests
- Refer to Pinpoint Test to be performed "On Board Diagnostics" based on the DTC displayed.
- Using a volt-ohmeter and the transaxle tester, perform the Pinpoint Tests as indicated in "On Board Diagnostics" based on the DTC which were displayed.
- Perform repairs as indicated by the Pinpoint Tests. Always retest and road test the vehicle after a repair.




TRANSAXLE FLUID TEMPERATURE (TFT) SENSOR
1. Set an ohmmeter to the 1,000 ohm range.
2. Connect the positive lead to the +TFT jack.
3. Connect the negative lead to the -TFT jack.
4. Record the resistance. Resistance will vary with temperature.
5. Refer to the chart for the valves.

Resistance Chart:

6. If out of range, refer to DTC P0712.