Charging System Indicator Troubleshooting

Charging System Indicator Circuit Troubleshooting
1. Turn the ignition switch OFF.
2. Check the 12 V battery.
Is the 12 V battery OK?
YES-Go to step 3.
NO-Charge or replace the 12 V battery, then go to step 3.
3. Check the IMA system for DTCs.
Are any DTCs indicated?
YES-Go to the DTC Troubleshooting.
NO-Go to step 4.
4. Turn the ignition switch ON (II).
Does the charging system indicator stay on?
YES-Go to step 5.
NO-Go to step 25.
5. Start the engine.
Does the charging system indicator go off?
YES-intermittent failure, system is ok at this time.
NO-Go to step 6.
6. Let the engine idle for 2 minutes, then check for DTCs.
Are any DTCs indicated?
YES-Go to DTC troubleshooting.
NO-Go to step 7.
7. Turn the ignition switch OFF.
8. Turn the battery module switch OFF.
9. Remove the IPU lid.
10. Turn the battery module switch ON.
11. Start the engine.





12. Measure voltage between DC-DC converter 8P connector terminal No. 6 and body ground.
Is there less than 1 V?
YES-Go to step 13.
NO-Go to step 19.
13. Turn the ignition switch OFF.
14. Turn the battery module switch OFF.
15. Disconnect MCM connector A (31P).





16. Check for continuity between the DC-DC converter 8P connector terminal No. 6 and body ground.
Is there continuity?
YES-Go to step 17.
NO-Update the MCM if it does not have the latest software, or substitute a known-good MCM, then recheck. If the symptom/indication goes away with a known-good MCM, replace the original MCM.
17. Disconnect the DC-DC converter 8P connector.





18. Check for continuity between DC-DC converter 8P connector terminal No. 6 and body ground.
Is there continuity?
YES-Repair short in the wire between the DC-DC converter and the MCM (A14).
NO-Replace the DC-DC converter.
19. Turn the ignition switch OFF.
20. Turn the battery module switch OFF.
21. Disconnect the DC-DC converter 8P connector.





22. Check for continuity between DC-DC converter 8P connector terminal No. 2 and body ground.
Is there continuity?
YES-Go to step 23.
NO-Replace the DC-DC converter.
23. Disconnect the gauge assembly connector B (22P).





24. Check for continuity between DC-DC converter 8P connector terminal No.2 and body ground.
Is there continuity?
YES-Repair short in the wire between the DC-DC converter and the gauge assembly.
NO-Replace the gauge assembly.
25. Turn the ignition switch OFF.
26. Turn the battery module switch OFF.
27. Remove the IPU lid.
28. Turn the ignition switch ON (II).





29. Measure voltage between DC-DC converter 8P connector terminal No.1 and body ground.
Is there battery voltage?
YES-Go to step 30.
NO-Go to step 42.





30. Measure voltage between DC-DC converter 8P connector terminal No. 6 and body ground.
Is there about 5 V?
YES-Go to step 31.
NO-Go to step 34.





31. Connect DC-DC converter 8P connector terminal No. 6 to body ground with a jumper wire.
32. Disconnect MCM connector A (31P).





33. Check for continuity between body ground and MCM connector terminal A14.
Is there continuity?
YES-Update the MCM if it does not have the latest software, or substitute a known-good MCM, then recheck. If the symptom/indication goes away with a known-good MCM, replace the original MCM.
NO-Repair open in the wire between the DC-DC converter and the MCM (A14).
34. Turn the ignition switch OFF.
35. Disconnect the DC-DC converter 8P connector.





36. Connect DC-DC converter 8P connector terminal No. 2 to body ground with a jumper wire.
37. Turn the ignition switch ON (II).
Does the charging system indicator stay on?
YES-Replace the DC-DC converter.
NO-Go to step 38.
38. Turn the ignition switch OFF.
39. Disconnect the gauge assembly 22P connector.





40. Connect gauge assembly 22P connector terminal No. 3 to body ground with a jumper wire.





41. Check for continuity between DC-DC converter 8P connector terminal No. 2 and body ground.
Is there continuity?
YES-Replace the gauge assembly.
NO-Repair open in the wire between the DC-DC converter and the gauge assembly.
42. Check the No. 4 ECU (ECM) (10 A) fuse.
Is the fuse OK?
YES-Repair open in the wire between No. 4 ECU (ECM) (10 A) fuse and the DC-DC converter.
NO-Go to step 43.





43. Check for continuity between body ground and DC-DC converter 8P connector terminal No. 1.
Is there continuity?
YES-Go to step 44.
NO-Replace the No. 4 ECU (ECM) (10 A) fuse.
44. Disconnect the DC-DC converter 8P connector.





45. Check for continuity between body ground and DC-DC converter 8P connector terminal No. 1.
Is there continuity?
YES-Repair short in the wire between No. 4 ECU (ECM) (10 A) fuse and the DC-DC converter.
NO-Replace the No. 4 ECU (ECM) (10 A) fuse and the DC-DC converter.