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| Illustration 1 | g00776399 |
Schematic for the Transmission Auto/Manual Switch | |
The transmission auto/manual switch has five inputs to the power train electronic control module (ECM). During normal operation, one input is grounded while the other inputs are open. The valid combinations for each switch position are shown in table 1 that follows. If an invalid combination is detected by the power train ECM, a circuit failure is present. This diagnostic code is recorded when the status of two or more inputs of the switch are grounded. The diagnostic code is set in 5 seconds. After the diagnostic code has been corrected, the diagnostic code will be clear within 1 second.
| Auto/Manual Switch Status | |||||
| Switch Position |
Man J1-29 |
Auto 4 J1-31 |
Auto 3 J1-33 |
Auto 2 J1-32 |
Auto 1-4 J2-10 |
| Auto 1-4 | O (1) | O | O | O | G (2) |
| Auto 2-2 | O | O | O | G | O |
| Auto 2-3 | O | O | G | O | O |
| Auto 2-4 | O | G | O | O | O |
| Manual | G | O | O | O | O |
| ( 1 ) | O means Open. |
| ( 2 ) | G means Grounded. |
Possible causes of this diagnostic code are listed:
- Failed harness
- Failed switch
System Response:
The machine response is listed:
- The autoshift is disabled.
Note: The following procedure can create other diagnostic codes that can be detected by the power train ECM. Ignore these created diagnostic codes and clear the created diagnostic codes when this diagnostic code is corrected.
Note: Ensure that the diagnostic code is active and that the diagnostic code indicator is active.
Test Step 1. Check for an Open Circuit.
- Ensure that the diagnostic code is active.
- Observe the ON/OFF status of the diagnostic code indicator.
- Disconnect the connector of the transmission auto/manual switch from the harness.
Expected Result:
The diagnostic code changes from "04" to "03".
Results:
- YES - The diagnostic code changes from "04" to "03". The transmission auto/manual switch or the harness of the transmission auto/manual switch has failed. Perform the previous test step again in order to verify the failure of the switch.
Repair: Repair the switch or replace the switch if the switch has failed. Repair the switch or replace the switch harness if the switch harness has failed.
Stop.
- NO - The diagnostic code does not change. The diagnostic code indicator remains active. The transmission auto/manual switch is not the cause of this diagnostic code. Proceed to test step 2.
Test Step 2. Check the Harness Circuit.
This test checks the continuity of the entire harness circuit that has failed. The transmission auto/manual switch which was previously checked in the previous test step is included in this test.
- Turn the key start switch and the disconnect switch to the OFF position.
- Reconnect the transmission auto/manual switch to the harness.
- Disconnect the harness from the power train ECM.
- At the harness connector for the power train ECM, check the continuity to ground of the open contacts and the grounded contact for each position of the transmission auto/manual switch. Activate and deactivate each position of the transmission auto/manual switch. Refer to table 1 for the correct status of the switch inputs.
Expected Result:
The continuity check does not agree with table 1.
Results:
- YES - The continuity check does not agree with the previous table. The harness circuit has failed. There is a short to ground in the harness between the power train ECM and the switch.
Repair: Repair the harness or replace the harness.
Stop.
- NO - The continuity check agrees with the previous table. The harness circuit is correct. It is unlikely that the power train ECM has failed. Exit this procedure and perform this test procedure again.
Repair: If the cause is not found, replace the power train ECM. Refer to Testing and Adjusting, "Electronic Control Module (Power Train) - Replace" for more information on replacing the power train ECM.
Stop.