Part 1
DLC Circuit Troubleshooting (Part 1)NOTE: Before you begin, make sure the HDS and its DLC cable are working properly.
1. Turn the ignition switch OFF.
2. Connect the HDS to the DLC.
NOTE: Make sure the HDS is properly connected to the DLC.
3. Turn the ignition switch ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES - Go to step 4.
NO - Go to step 20.
4. Check for Temporary DTCs or DTCs in the PGM-FI system with the HDS.
Are any Temporary DTCs or DTCs indicated?
YES - Go to the indicated DTCs troubleshooting.
NO - Go to step 5.
5. Turn the ignition switch OFF.
6. Turn the ignition switch ON (II), and watch the SRS indicator.
Does the SRS indicator stay on?
YES - Go to the SRS system's general troubleshooting information.
NO - Go to step 7.
7. Turn the ignition switch OFF.
8. Turn the ignition switch ON (II), and watch the TPMS indicator.
Does the TPMS indicator stay on?
YES - Go to the TPMS system's general troubleshooting information.
NO - Go to step 9.
9. Turn the ignition switch OFF.
10. Turn the ignition switch ON (II), and watch the VSA indicator.
Does the VSA indicator stay on?
YES - Go to the VSA system's general troubleshooting information.
NO - Go to step 11.
11. Turn the ignition switch OFF.
12. Turn the ignition switch ON (II), and watch the immobilizer indicator.
Does the immobilizer indicator stay on or flash?
YES - Go to the immobilizer system's troubleshooting.
NO - Go to step 13.
13. Check for B-CAN system DTCs without the HDS.
Are any B-CAN DTCs indicated?
YES - Go to the indicated DTCs troubleshooting.
NO - Go to step 14.
14. Turn the ignition switch OFF.
15. Disconnect the HDS from the DLC.
16. Check for continuity between body ground and DLC terminals No. 1 and No. 7 individually.
Is there continuity?
YES - Go to step 17.
NO - Go to step 18.
17. Continue to check for continuity between DLC terminals No. 1 and No. 7 and body ground individually, while disconnecting these parts, one at a time:
- SRS unit connector A (28P)
- VSA modulator-control unit 37P connector
- Immobilizer control unit 7P connector
- TPMS control unit connector B (20P)
Does continuity go away when one of the above components is disconnected?
YES - Replace the part that caused an open when it was disconnected.
NO - Repair short in the wire between the DLC No. 7 (K-line) and the VSA modulator-control unit, the SRS unit, the audio unit, or the TPMS control unit or DLC No. 1 (DIAG-H line) and the immobilizer control unit.
18. Connect DLC terminals No. 1 and No. 7 to body ground with a jumper wire.
19. Check for continuity between body ground and these connector terminals:
Is there continuity between the DLC terminal and each of the terminals in the chart?
YES - Replace the unit that does not communicate with the HDS.
NO - Repair open in the wire between the DLC (K-line or DIAG-H line) and the appropriate connector.
20. Check for B-CAN system DTCs without the HDS.
Is DTC B1168, B1169, and/or B1178 indicated?
YES - Go to step 34.
NO - Go to step 21.
21. Turn the ignition switch OFF.
22. Disconnect the HDS from the DLC.
23. Measure voltage between DLC terminal No. 16 and body ground.
Is there battery voltage?
YES - Go to step 24.
NO - Repair open in the wire between DLC terminal No. 16 and the No. 8 FI ECU (ECM/PCM) (15 A) fuse in the under-hood fuse/relay box.
24. Measure voltage between DLC terminals No. 4 and No. 16.
Is there battery voltage?
YES - Go to step 25.
NO - Repair open in the wire between DLC terminal No. 4 and G501.
25. Connect the HDS to the DLC.
26. Jump the SCS line with the HDS.
27. Disconnect ECM/PCM connector E (31P).
28. Disconnect the HDS from the DLC.
29. Connect DLC terminal No. 6 to body ground with a jumper wire.
30. Check for continuity between ECM/PCM connector terminal E15 and body ground.
Is there continuity?
YES - Go to step 31.
NO - Repair open in the wire between the ECM/PCM (E15) and DLC terminal No. 6.
31. Disconnect the jumper wire.
32. Connect DLC terminal No. 14 to body ground with a jumper wire.
33. Check for continuity between ECM/PCM connector terminal E26 and body ground.
Is there continuity?
YES - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.
NO - Repair open in the wire between the ECM/PCM (E26) and DLC terminal No. 14.
34. Try to start the engine.
Does the engine start and idle smoothly?
YES - Go to the F-CAN circuit troubleshooting.
NO - Go to step 35.
35. Turn the ignition switch OFF.
36. Check the No. 23 +B IG1 MAIN (50 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES - Repair open in the wire between the No. 23 +B IG1 MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to DLC circuit troubleshooting (part 2).
NO - Repair short in the wire between the No. 23 +B IG1 MAIN (50 A) fuse and the ignition switch. Also replace the No. 23 +B IG1 MAIN (50 A) fuse.