DLC Circuit Troubleshooting (PGM-FI System)
DLC Circuit Troubleshooting
NOTE: If you suspect the HDS or HDS DLC cable may be the source of the communication problem, verify that they are working properly by connecting them to a known-good, like vehicle and system, and checking for communication problem.
1. Turn the ignition switch to LOCK (0).
2. Connect the HDS to the DLC.
3. Turn the ignition switch to ON (II), and read the HDS.
Does the HDS identify the vehicle?
YES -
Go to step 4.
NO -
Go to step 25.
4. Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.
Are any Pending or Confirmed DTCs indicated?
YES -
Go to the indicated DTC's troubleshooting.�
NO -
- If the HDS does not communicate with the SRS system, go to step 5.
- If the HDS does not communicate with the VSA system, go to step 7.
- If the HDS does not communicate with the ABS system, go to step 9.
- If the HDS does not communicate with the EPS system, go to step 11.
- If the HDS does not communicate with the TPMS system, go to step 13.
- If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step 15.
- If the HDS does not communicate with the BODY ELECTRICAL system, go to step 17.
5. Turn the ignition switch to LOCK (0).
6. Turn the ignition switch to ON (II), and watch the SRS indicator.
Does the SRS indicator come on and go off?
YES -
Go to step 19.
NO -
Go to the SRS symptom troubleshooting for an SRS indicator that stays on with no stored DTCs Symptom Troubleshooting.�
7. Turn the ignition switch to LOCK (0).
8. Turn the ignition switch to ON (II), and watch the VSA indicator.
Does the VSA indicator come on and go off?
YES -
Go to step 19.
NO -
Go to the VSA symptom troubleshooting for an ABS indicator, brake system indicator, and VSA indicator that do not go off Symptom Troubleshooting.�
9. Turn the ignition switch to LOCK (0).
10. Turn the ignition switch to ON (II), and watch the ABS indicator.
Does the ABS indicator come on and go off?
YES -
Go to step 19.
NO -
Go to the ABS symptom troubleshooting for an ABS indicator and a brake system indicator that do not go off Symptom Troubleshooting.�
11. Turn the ignition switch to LOCK (0).
12. Start the engine, and watch the EPS indicator.
Does the EPS indicator come on and go off?
YES -
Go to step 19.
NO -
Go to the EPS symptom troubleshooting for an EPS indicator that does not go off with no stored DTCs EPS Indicator Does Not Go Off, And No DTCs Are Stored.�
13. Turn the ignition switch to LOCK (0).
14. Turn the ignition switch to ON (II), and watch the TPMS indicator.
Does the TPMS indicator come on and go off?
YES -
Go to step 19.
NO -
Go to the TPMS symptom troubleshooting for TPMS indicator does not go off, and no DTC stored Symptom Troubleshooting.�
15. Turn the ignition switch to LOCK (0).
16. Turn the ignition switch to ON (II), and watch the immobilizer indicator.
Does the immobilizer indicator stay on or flash?
YES -
Go to the immobilizer system's troubleshooting Immobilizer System Symptom Troubleshooting Information.�
NO -
Go to step 19.
17. Do the gauge self-diagnostic function Initial Inspection and Diagnostic Overview.
18. Check the gauge display.
Is Error 2 indicated?
YES -
Check for B-CAN system DTCs.�
NO -
Go to step 19.
19. Turn the ignition switch to LOCK (0), then do the 12 volt battery terminal disconnection procedure Procedures, and wait at least 3 minutes before continuing.
20. Disconnect the HDS from the DLC.
21. Check for continuity between DLC terminal No. 7 and body ground.
Is there continuity?
YES -
Go to step 22.
NO -
Go to step 23.
22. Continue to check for continuity between DLC terminal No. 7 and body ground, while disconnecting these parts, one at a time:
- SRS unit connector A (39P)
- VSA modulator-control unit 47P connector
- ABS modulator-control unit 47P connector
- EPS control unit connector C (16P)
- TPMS control unit 20P connector
- Immobilizer-keyless control unit 7P connector
- Audio-navigation unit 24P connector
- Under-dash fuse/relay box connector Q (16P)
Does continuity go away when one of the above connectors is disconnected?
YES -
Replace the part that caused continuity go away when it was disconnected.�
NO -
Repair a short in the wire between the DLC (K-line) and the VSA modulator-control unit, the ABS control unit, the SRS unit, the EPS control unit, the immobilizer-keyless control unit, the audio-navigation unit, or the under-dash fuse/relay box.�
23. Connect DLC terminal No. 7 to body ground with a jumper wire.
24. Check for continuity between body ground and these connector terminals:
Is there continuity between body ground and each of the terminals in the chart?
YES -
Replace the part that does not communicate with the HDS.�
NO -
Repair an open in the wire between the DLC (K-line) and the appropriate connector.�
25. Check for B-CAN system DTCs without the HDS.
Is DTC U0029 and/or U0100 indicated?
YES -
Go to step 36.
NO -
Go to step 26.
26. Turn the ignition switch to LOCK (0).
27. Disconnect the HDS from the DLC.
28. Measure the voltage between DLC terminal No. 16 and body ground.
Is there battery voltage?
YES -
Go to step 29.
NO -
Repair an open in the wire between DLC terminal No. 16 and the No. 1 BACK UP (10 A) fuse in the under-dash fuse/relay box.�
29. Measure the voltage between DLC terminals No. 4 and No. 16.
Is there battery voltage?
YES -
Go to step 30.
NO -
Repair an open in the wire between DLC terminal No. 4 and body ground (G502).�
30. Connect the HDS to the DLC.
31. Jump the SCS line with the HDS.
32. Disconnect PCM connector A (44P).
33. Disconnect the HDS from the DLC.
34. Check for continuity between PCM connector terminal A36 and DLC terminal No. 6.
Is there continuity?
YES -
Go to step 35.
NO -
Repair an open in the wire between the PCM (A36) and DLC terminal No. 6.�
35. Check for continuity between PCM connector terminal A37 and DLC terminal No. 14.
Is there continuity?
YES -
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 and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM.�
NO -
Repair an open in the wire between the PCM (A37) and DLC terminal No. 14.�
36. Try to start the engine.
Does the engine start and idle smoothly?
YES -
Go to F-CAN circuit troubleshooting F-CAN Circuit Troubleshooting.�
NO -
Go to step 37.
37. Turn the ignition switch to LOCK (0).
38. Check the No. 60 IGSW (50 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES -
Repair an open in the wire between the No. 60 IGSW (50 A) fuse and the ignition switch. If the wire is OK go to step 39.
NO -
Repair a short in the wire between the No. 60 IGSW (50 A) fuse and the under-dash fuse/relay box. Also replace the No. 60 IGSW (50 A) fuse.�
39. Inspect the No. 39 IGP (15 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES -
Go to step 46.
NO -
Go to step 40.
40. Remove the blown No. 39 IGP (15 A) fuse from the under-dash fuse/relay box.
41. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
42. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 2 and No. 3 individually.
Is there continuity?
YES -
Replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal And Installation (Except Canada Models).�
NO -
Go to step 43.
43. While disconnecting each of the parts or connectors below, one at a time, check for continuity between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
- PGM-FI main relay 2
- PCM connector A (44P)
- Each injector 2P connector
- CMP sensor 3P connector
- CKP sensor 3P connector
- Electronic throttle control system (ETCS) control relay
Does continuity go away when one of the above parts or components is disconnected?
YES -
Replace the part that made the short to body ground go away when disconnected. If the part is the PCM, update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM Service and Repair. Also replace the No. 39 IGP (15 A) fuse.�
NO -
Go to step 44.
44. Disconnect the connectors from these parts:
- PGM-FI main relay 2
- PCM connector A (44P)
- Each injector 2P connector
- CMP sensor 3P connector
- CKP sensor 3P connector
- Electronic throttle control (ETCS) control relay
45. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Repair a short in the wire between PGM-FI main relay 1 and each part. Also replace the No. 39 IGP (15 A) fuse.�
NO -
Replace PGM-FI main relay 1. Also replace the No. 39 IGP (15 A) fuse.�
46. Inspect the No. 20 FUEL PUMP (15 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES -
Go to step 56.
NO -
Go to step 47.
47. Remove the blown No. 20 FUEL PUMP (15 A) fuse from the under-dash fuse/relay box.
48. Remove PGM-FI main relay 2 (A) from the auxiliary under-hood fuse/relay box.
49. Test PGM-FI main relay 2.
Is the relay OK?
YES -
Go to step 50.
NO -
Replace PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP (15 A) fuse.�
50. Check for continuity between PGM-FI main relay 2 4P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Go to step 51.
NO -
Go to step 54.
51. Jump the SCS line with the HDS.
52. Disconnect PCM connector C (44P).
53. Check for continuity between PCM connector terminal C36 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the No. 20 FUEL PUMP (15 A) fuse and the PCM (C36) or PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP (15 A) fuse.�
NO -
Replace the No. 20 FUEL PUMP (15 A) fuse, and update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM Service and Repair.�
54. Disconnect the fuel pump 4P connector Fuel Tank Unit Removal/Installation.
55. Check for continuity between fuel pump 4P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the fuel pump and PGM-FI main relay 2. Also replace the No. 20 FUEL PUMP (15 A) fuse.�
NO -
Check the fuel pump, and replace it if needed Fuel Pump/Fuel Gauge Sending Unit Replacement. Also replace the No. 20FUEL PUMP (15 A) fuse.�
56. Jump the SCS line with the HDS.
57. Disconnect PCM connectors A (44P) and C (44P).
58. Turn the ignition switch to ON (II).
59. Measure the voltage between PCM connector terminal C36 and body ground.
Is there battery voltage?
YES -
Go to step 60.
NO -
Repair an open in the wire between the No. 20 FUEL PUMP (15 A) fuse and the PCM (C36).�
60. Measure the voltage between PCM connector terminal A6 and body ground.
Is there battery voltage?
YES -
Go to step 66.
NO -
Go to step 61.
61. Turn the ignition switch to LOCK (0).
62. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
63. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 3 and body ground.
Is there battery voltage?
YES -
Go to step 64.
NO -
Replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal And Installation (Except Canada Models).�
64. Connect PGM-FI main relay 1 4P connector terminal No. 4 to body ground with a jumper wire.
65. Check for continuity between PCM connector terminal A6 and body ground.
Is there continuity?
YES -
Test PGM-FI main relay 1 Testing and Inspection. If the relay is OK, update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM Service and Repair.�
NO -
Repair an open in the wire between the PCM(A6) and PGM-FI main relay 1.�
66. Turn the ignition switch to LOCK (0).
67. Open the fuse access panel (A), then remove PGM-FI main relay 1 (B) from the under-dash fuse/relay box.
68. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
Is there battery voltage?
YES -
Go to step 69.
NO -
Replace the under-dash fuse/relay box Under-Dash Fuse/Relay Box Removal And Installation (Except Canada Models).�
69. Connect PGM-FI main relay 1 4P connector terminal No. 1 to body ground with a jumper wire.
70. Check for continuity between body ground and PCM connector terminals A8 and A43 individually.
Is there continuity?
YES -
Remove the jumper wire, then go to step 71.
NO -
Repair an open in the wire between the PCM (A8, A43) and PGM-FI main relay 1.�
71. Disconnect PCM connector B (44P).
72. Check for continuity between body ground and PCM connector terminals B1, B36, C2, C40, and C44 individually.
Is there continuity?
YES -
Go to step 73.
NO -
Repair an open in the wire between the PCM (B1, B36, C2, C40, C44) and G101.�
73. Check for continuity between PCM connector terminal C39 and body ground.
Is there continuity?
YES -
Go to step 74.
NO -
Go to step 75.
74. Continue to check for continuity between PCM connector terminal C39 and body ground, while disconnecting these connectors, one at a time:
- MAP sensor 3P connector
- CVT output (driven pulley) speed sensor 3P connector
Does continuity go away when one of the above connectors is disconnected?
YES -
Replace the part that made the short to body ground go away when disconnected.�
NO -
Repair a short in the wire between the PCM(C39) and the MAP sensor or the CVT output (driven pulley) speed sensor.�
75. Check for continuity between PCM connector terminal B6 and body ground.
Is there continuity?
YES -
Go to step 76.
NO -
Go to step 77.
76. Continue to check for continuity between PCM connector terminal B6 and body ground, while disconnecting these connectors, one at a time:
- Rocker arm oil pressure sensor A and B 3P connectors
- EGR valve 5P connector
- CVT input (drive pulley) speed sensor 3P connector
- Vehicle speed sensor 3P connector
Does continuity go away when one of the above connectors is disconnected?
YES -
Replace the part that made the short to body ground go away when disconnected.�
NO -
Repair a short in the wire between the PCM (B6) and rocker arm oil pressure sensor A and B, the EGR valve, the CVT input (drive pulley) speed sensor, the CVT speed sensor.�
77. Check for continuity between PCM connector terminal C12 and body ground.
Is there continuity?
YES -
Go to step 78.
NO -
Go to step 79.
78. Continue to check for continuity between PCM connector terminal C12 and body ground, while disconnecting the throttle body 6P connector.
Is there continuity?
YES -
Repair a short in the wire between the PCM (C12) and the throttle body.�
NO -
Replace the throttle body Removal and Replacement.�
79. Check for continuity between PCM connector terminal A25 and body ground.
Is there continuity?
YES -
Go to step 80.
NO -
Go to step 81.
80. Continue to check for continuity between PCM connector terminal A25 and body ground, while disconnecting the APP sensor 6P connector.
Is there continuity?
YES -
Repair a short in the wire between the PCM (A25) and APP sensor A.�
NO -
Replace the accelerator pedal module Service and Repair.�
81. Check for continuity between PCM connector terminal A24 and body ground.
Is there continuity?
YES -
Go to step 82.
NO -
Go to step 83.
82. Continue to check for continuity between PCM connector terminal A24 and body ground, while disconnecting the APP sensor 6P connector.
Is there continuity?
YES -
Repair a short in the wire between the PCM (A24) and APP sensor B.�
NO -
Replace the accelerator pedal module Service and Repair.�
83. Check for continuity between PCM connector terminal A19 and body ground.
Is there continuity?
YES -
Go to step 84.
NO -
Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then recheck. If the symptom/indication goes away and the PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the PCM was substituted, replace the original PCM Service and Repair.�
84. Continue to check for continuity between PCM connector terminal A19 and body ground, while disconnecting these connectors, one at a time:
- A/C pressure sensor 3P connectors
- Brake booster pressure sensor A 3P connector
- Brake booster pressure sensor B 3P connector
- FTP sensor 3P connector
Does continuity go away when one of the above connectors is disconnected?
YES -
Repair the part that made the short to body ground go away when disconnected.�
NO -
Repair a short in the wire between the PCM (A19) and brake booster pressure sensor A, brake booster pressure sensor B, the A/C pressure sensor.�