Malfunction Indicator Lamp: Testing and Inspection
MIL Circuit Troubleshooting1. Turn the ignition switch ON (II).
2. Do the gauge self-diagnostic function.
Does the MIL indicator flash?
YES - Go to step 3.
NO - Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module.
3. Turn the ignition switch OFF.
4. Turn the ignition switch ON (II), and watch the MIL.
Does the MIL stay off?
YES - Go to step 17.
NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Turn the ignition switch ON (II), wait 20 seconds, and watch the MIL.
Does the MIL stay on or flash more than 5 times?
YES - Go to step 7.
NO - The MIL circuit is OK.
7. Turn the ignition switch OFF.
8. Connect the HDS.
9. Turn the ignition switch ON (II), and read the HDS.
Does the HDS communicate with the PCM?
YES - Go to step 10.
NO - Go to "DLC Circuit Troubleshooting". If no problem is found in the DLC troubleshooting, go to step 21.
10. Check for Temporary DTCs or DTCs with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - Go to the indicated DTC's troubleshooting.
NO - Go to step 11.
11. Check the MIL in the DATA LIST with the HDS.
Does it indicate ON?
YES - Go to step 12.
NO - Substitute a known-good gauge control module, and recheck. If the MIL circuit is OK, replace the original gauge control module.
12. Check the SCS in the DATA LIST with the HDS.
Is a short indicated?
YES - Go to step 13.
NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
13. Turn the ignition switch OFF.
14. Jump the SCS line with the HDS.
15. Disconnect PCM connector A (44P).
16. Check for continuity between PCM connector terminal A31 and body ground.
Is there continuity?
YES - Repair short in the wire between the PCM (A31) and the DLC.
NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
17. Try to start the engine.
Does the engine start and idle smoothly?
YES - Go to step 18.
NO - Go to step 22.
18. Turn the ignition switch OFF.
19. Connect the HDS.
20. Turn the ignition switch ON (II), and read the HDS.
Does the HDS communicate with the PCM?
YES - Go to step 22.
NO - Go to "DLC Circuit Troubleshooting". If no problem is found in the DLC troubleshooting, go to step 21.
21. Check for Temporary DTCs or DTCs with the HDS.
Is DTC U0073 and/or U0155 indicated?
YES - Go to the indicated DTC troubleshooting.
NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
22. Turn the ignition switch OFF.
23. Inspect the No.42 +B IG MAIN (50 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Repair open in the wire between the No.42 +B IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 24.
NO - Repair short in the wire between No.42 +B IG MAIN (50 A) fuse and the driver's under-dash fuse/relay box. Also replace the No.42 +B IG MAIN (50 A) fuse.
24. Inspect the No.46 ACGS (15 A) fuse in the underhood fuse/relay box.
Is the fuse OK?
YES - Go to step 31.
NO - Go to step 25.
25. Remove the blown No.46 ACGS (15 A) fuse from the under-hood fuse/relay box.
26. Remove PGM-FI main relay 1 (FI MAIN) (A).
27. Check for continuity between body ground and PGM-FI main relay 1 (FI MAIN) 4P connector terminals No.1 and No.3 individually.
Is there continuity?
YES - Repair short in the wire between the No.46 ACGS (15 A) and PGM-FI main relay 1 (FI MAIN). Also replace the No.46 ACGS (15 A) fuse.
NO - Go to step 28.
28. Disconnect each of the components or connectors below, one at a time, and check for continuity between PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.2 and body ground.
- PGM-FI main relay 2 (FUEL PUMP)
- PCM connector B (44P)
- Each injector 2P connector
- Camshaft position (CMP) sensor 3P connector
- Crankshaft position (CKP) sensor A/B 6P connector
- Electronic throttle control system (ETCS) control relay
Is there continuity?
YES - Go to step 29.
NO - Replace the component that made the short to body ground go away when disconnected. If the item is the PCM, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM. Also replace the No.46 ACGS (15 A) fuse.
29. Disconnect the connectors of all these components.
- PGM-FI main relay 2 (FUEL PUMP)
- PCM connector B (44P)
- Injectors
- Camshaft position (CMP) sensor
- Crankshaft position (CKP) sensor A/B
- Electronic throttle control system (ETCS) control relay
30. Check for continuity between PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.2 and body ground.
Is there continuity?
YES - Repair short in the wire between the PGM-FI main relay 1 (FI MAIN) and each item. Also replace the No.46 ACGS (15 A) fuse.
NO - Replace PGM-FI main relay 1 (FI MAIN). Also replace the No.46 ACGS (15 A) fuse.
31. Inspect the No.1 FUEL PUMP (15 A) fuse in the driver's under-dash fuse/relay box.
Is the fuse OK?
YES - Go to step 44.
NO - Go to step 32.
32. Remove the blown No.1 IG FUEL PUMP (15 A) fuse in the driver's under-dash fuse/relay box.
33. Jump the SCS line with the HDS.
34. Disconnect PCM connector B (44P).
35. Check for continuity between PCM connector terminal B37 and body ground.
Is there continuity?
YES - Go to step 36.
NO - Replace the No.1 FUEL PUMP (15 A) fuse, and update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.
36. Remove PGM-FI main relay 2 (FUEL PUMP) (A).
37. Check for continuity between PCM connector terminal B37 and body ground.
Is there continuity?
YES - Repair short in the wire between the No.1 FUEL PUMP (15 A) fuse and the PCM (B37), or between the No.1 FUEL PUMP (15 A) fuse and PGM-FI main relay 2 (FUEL PUMP). Also replace the No.1 FUEL PUMP (15 A) fuses
NO - Go to step 38.
38. Remove the driver's side second row seat.
39. Remove the access panel from the floor.
40. Disconnect the fuel pump 5P connector.
41. Check for continuity between fuel pump 5P connector terminal No.5 and body ground.
Is there continuity?
YES - Repair short in the wire between the fuel pump and PGM-FI main relay 2 (FUEL PUMP). Also replace the No.1 FUEL PUMP (15 A) fuse.
NO - Go to step 42.
42. Reinstall PGM-FI main relay 2 (FUEL PUMP) (A).
43. Check for continuity between fuel pump 5P connector terminal No.5 and body ground.
Is there continuity?
YES - Replace PGM-FI main relay 2 (FUEL PUMP). Also replace the No.1 FUEL PUMP (15 A) fuse.
NO - Check the fuel pump, and replace it if necessary. Also replace the No.1 FUEL PUMP (15 A) fuse.
44. Jump the SCS line with the HDS.
45. Disconnect PCM connector A (44P) and B (44P).
46. Turn the ignition switch ON (II).
47. Measure voltage between PCM connector terminal B37 and body ground.
Is there battery voltage?
YES - Go to step 48.
NO - Repair open in the wire between the No.1 FUEL PUMP (15 A) fuse and the PCM (B37).
48. Measure voltage between PCM connector terminal A6 and body ground.
Is there battery voltage?
YES - Go to step 54.
NO - Go to step 49.
49. Turn the ignition switch OFF.
50. Remove PGM-FI main relay 1 (FI MAIN) (A).
51. Measure voltage between PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.3 and body ground.
Is there battery voltage?
YES - Go to step 52.
NO - Repair open in the wire between the No.46 ACGS (15 A) fuse and PGM-FI main relay 1 (FI MAIN)
52. Connect PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.4 to body ground with a jumper wire.
53. Check for continuity between PCM connector terminal A6 and body ground.
Is there continuity?
YES - Test PGM-FI main relay (FI MAIN). If the relay is OK, update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known- good PCM, replace the original PCM.
NO - Repair open in the wire between PGM-FI main relay 1 (FI MAIN) and the PCM (A6).
54. Reconnect PCM connector A (44P).
55. Turn the ignition switch ON (II).
56. Measure voltage between body ground and PCM connector terminal B3.
Is there battery voltage?
YES - Go to step 64.
NO - Go to step 57
57. Turn the ignition switch OFF.
58. Remove PGM-FI main relay 1 (FI MAIN) (A).
59. Turn the ignition switch ON (II).
60. Measure voltage between PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.1 and body ground.
Is there battery voltage?
YES - Go to step 61.
NO - Repair open in the wire between the No.8 ACGS (15 A) fuse and PGM-FI main relay 1 (FI MAIN).
61. Turn the ignition switch OFF.
62. Connect PGM-FI main relay 1 (FI MAIN) 4P connector terminal No.2 to body ground with a jumper wire.
63. Check for continuity between PCM connector terminal 83 and body ground.
Is there continuity?
YES - Replace PGM-FI main relay 1 (FI MAIN).
NO - Repair open in the wire between PGM-FI main relay 1 (FI MAIN) and the PCM (B3).
64. Turn the ignition switch OFF.
65. Disconnect PCM connector A, B, and C.
66. Check for continuity between body ground and PCM connector terminals A22, B1, B36, B43, C1, and C40 individually.
Is there continuity?
YES - Go to step 67.
NO - Repair open in the wire(s) between PCM (A22, B1, B36, B43, C1, C40) and body ground (G101).
67. Disconnect the connector from each of these sensors, one at a time, and check for continuity between body ground and PCM connector terminal A19, A24, A25, B18, B19, and C13 individually.
- MAP sensor
- Output shaft (countershaft) speed sensor
- EGR valve position sensor
- Input shaft (mainshaft) speed sensor
- APP Sensor A
- APP sensor B
- TP sensor
- FTP sensor
Is there continuity?
YES - Repair short to ground in the wire between PCM and the following sensors.
- MAP sensor
- Output shaft (countershaft) speed sensor
- EGR valve position sensor
- Input shaft (mainshaft) speed sensor
- APP sensor A
- APP sensor B
- TP sensor
- FTP sensor
NO - Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the symptom/indication goes away with a known-good PCM, replace the original PCM.