DTC 42

DTC 42: Motor Commutation Signal Problem
1. Reset the MCM.
2. Turn the ignition switch ON (II).
Is DTC 42 indicated?
YES- Go to step 3.
NO- Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the motor commutation sensor and at the MCM.
3. Turn the ignition switch OFF.
4. Disconnect the motor commutation sensor 10P connector.
5. Turn the ignition switch ON (II).





6. In the engine compartment, measure voltage between the motor commutation sensor 10P connector terminals No. 5 and No. 9, No. 4 and No. 8, and No. 7 and No. 10.
Is there about 5 V?
YES- Go to step 13.
NO- Go to step 7.





7. Measure voltage between body ground and the motor commutation sensor 10P connector terminals No. 5, No. 4, and No. 7.
Is there about 5 V?
YES- Repair open in the wire between the motor commutation sensor and the MCM (D4, D10, D16).
NO- Go to step 8.
8. Turn the ignition switch OFF.
9. Turn the battery module switch OFF.
10. Remove the IPU lid.
11. Turn the ignition switch ON (II).





12. Measure voltage between the MCM connector terminals D1 and D4, D6 and D10, and D13 and D16.
YES- Repair open in the wire between the motor commutation sensor and the MCM (D1, D6, D13).
NO- Substitute a known-good MCM and commutation sensor and recheck. If the symptom/ indication goes away, replace the original MCM and commutation sensor.
13. Turn the ignition switch OFF.





14. Check for continuity between body ground and the motor commutation sensor 10P connector terminals No. 1, No. 2, and No. 3 individually.
Is there continuity?
YES- Go to step 15.
NO- Go to step 17.
15. Disconnect MCM connector D.
16. Check for continuity between body ground and the motor commutation sensor 10P connector terminals No. 1, No. 2, and No. 3 individually.
Is there continuity?
YES- Repair short in the wire between the motor commutation sensor and the MCM (D2, D8, D15).
NO- Replace the MCM.
17. Turn the battery module switch OFF.
18. Remove the IPU lid.





19. Connect the MCM connector terminals D2, D8, and D15 to body ground with a jumper wire.





20. Check for continuity between body ground and the motor commutation sensor 10P connector terminals No. 1, No. 2, and No. 3 individually.
Is there continuity?
YES- Substitute a known-good MCM and the motor commutation sensor, and recheck. If the symptom/indication goes away, replace the original MCM and the motor commutation sensor.
NO- Repair open in the wire between the motor commutation sensor and the MCM (D2, D8, D15).