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A/T Gear Position Signal Circuit Troubleshooting

A/T Gear Position Signal Circuit Troubleshooting

CVT model

1. Turn the ignition switch ON (II).
2. Look at the A/T gear position indicator and select each position.

Does the indicator light properly?

YES - Go to step 3.

NO - Do the A/T gear position indicator input test.

3. Turn the ignition switch OFF.
4. Remove the gauge assembly from the dashboard. Disconnect the gauge assembly 10P connector.
5. Disconnect TCM connector A (26P).
6. Turn the ignition switch ON (II).




7. Measure voltage between ECM connector terminals B14 and B20 with the transmission not in N or P position.

Is there battery voltage?

YES - Go to step 11.

NO - Go to step 8.

8. Turn the ignition switch OFF.
9. Disconnect ECM connector B (24P).




10. Check for continuity between ECM connector terminal B14 and body ground.

Is there continuity?

YES - Repair short in the wire between the ECM (B14) and the A/T gear position switch, the TCM (A10), or the gauge assembly.

NO - Update the ECM if it does not have the latest software, or substitute a known-good ECM, then recheck. If the symptom/indication goes away with a known-good ECM, replace the original ECM.

11. Turn the ignition switch OFF.
12. Reconnect the gauge assembly 10P connector.
13. Reconnect TCM connector A (26P).
14. Turn the ignition switch ON (II).




15. Measure voltage between ECM connector terminals B14 and B20 with the transmission in N or P position.

Is there less than 1.0 V?

YES - Go to step 16.

NO - Repair open in the wire between the ECM (B14) and the A/T gear position switch.




16. Measure voltage between ECM connector terminals B16 and B20 with the transmission in D position.

Is there less than 1.0V?

YES - Go to step 17.

NO - Repair open in the wire between the ECM (B16) and the A/T gear position switch.




17. Measure voltage between ECM connector terminals B16 and B20 with the transmission in N or P position.

Is there battery voltage?

YES - Go to step 18.

NO - Repair short in the wire between the ECM (B16) and the A/T gear position switch.




18. Measure voltage between ECM connector terminals B20 and B24 with the transmission in R position.

Is there less than 1.0 V?

YES - Go to step 19.

NO - Repair open in the wire between the ECM (B24) and the A/T gear position switch.




19. Measure voltage between ECM connector terminals B20 and B24 with the transmission in N or P position.

Is there battery voltage?

YES - The A/T gear position signal is OK.

NO - Repair short in the wire between the ECM (B24) and the A/T gear position switch.