DTC 331

FF. DTC 3-3-1
3-3-1 Short-circuit to supply in solenoid SL circuit

Principle of operation

Solenoid SL controls the transmission lock-up function when supplied with battery voltage. This is supplied by the TCM, which delivers engagement and disengagement signals based on the vehicle speed, throttle position and driving mode.

Fault description

A short-circuit to supply has occurred at some point in the solenoid SL control circuit and the solenoid is energized permanently, preventing correct operation of the lock-up function.





Circuit description

The circuit consists of the TCM, a number of connectors and solenoid SL in the transmission.





1
Testing solenoid SL in test mode 4

- Move gear selector lever to position P.

Test solenoid SL in test mode 4 use stethoscope to hear solenoid click more clearly. Displaying & Reading Trouble Codes

- If solenoid does not click, fault is permanent.
- If solenoid clicks, fault is occurring only intermittently under particular conditions, making it considerably more difficult to locate.

In both cases, fault is probably due to short-circuit between leads.





2
Measuring voltage with TCM disconnected

- Switch off ignition.
- Connect break-out box to wiring only.
- Switch on ignition.

Measure voltage across terminals # 26 (SL) and # 12 (SG)

- If instrument indicates 0 V, wiring is OK. Proceed to step 4.
- If instrument indicates battery voltage, short-circuit is between lead and other live lead. Proceed to step 3.

3
Measuring voltage with connector open

- Measure with ignition on and break-out box connected as in previous step.
- Open connector E at transmission.

Repeat measurement across terminals # 26 (SL) and # 12 (SG).

- If instrument indicates battery voltage, fault is in wiring between connector E and TCM.
- If instrument indicates 0 V, fault is in harness between connector E and solenoid SL. Replace harness.
Return to Testing and Inspection. Diagnostic Procedures






4
Measuring voltage in leads

- Switch off ignition.
- Measure with break-out box connected to wiring as before.
- Open connector E at transmission.

Repeat voltage measurement across # 26 (SL) and # 12 (SG).

- If instrument still indicates battery voltage, fault is in leads between connector and TCM.
- If instrument indicates approx. 0 V, fault is in harness between connector and solenoid SL. Replace harness.
Return to Testing and Inspection. Diagnostic Procedures






5
Measuring voltage with TCM in circuit

- Switch off ignition.
- Connect break-out box between TCM and wiring.
- Select driving mode E.
- Move gear selector lever to position D.
- Switch on ignition.

Measure voltage across terminals # 26 (SL) and # 12 (SG).

- Instrument should indicate approx. 0 V.
If reading is correct, return to Testing and inspection. AT / DTC Codes (Transmission Control Module)

Incorrect reading indicates TCM fault.

6
Conclusions

Step 2 incorrect - fault in leads.
Steps 2 and 4 correct - intermittent fault.
Step 2 correct and step 4 incorrect - fault in TCM.