Data Link Connector: Testing and Inspection
DLC Circuit Troubleshooting
NOTE: If you suspect the HDS or the 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 problems.
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 -
Go to step 5.
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 -
- Without VSA: Go to step 7.
- With VSA: Go to step 9.
NO -
Go to the SRS general troubleshooting information Reading and Clearing Diagnostic Trouble Codes.�
7. Turn the ignition switch to LOCK (0).
8. 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 11.
NO -
Go to the symptom troubleshooting for ABS indicator and brake system indicator 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 VSA indicator.
Does the VSA indicator come on and go off?
YES -
Go to step 11.
NO -
Go to the symptom troubleshooting for ABS indicator, brake system indicator, and VSA indicator 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 13.
NO -
Go to the symptom troubleshooting for EPS indicator does not go off, and no DTCs are stored 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 immobilizer indicator.
Does the immobilizer indicator stay on or flash?
YES -
Go to the immobilizer system's troubleshooting Immobilizer System Symptom Troubleshooting Information.�
NO -
- With TPMS: Go to step 15.
- Without TPMS: Go to step 17.
15. Turn the ignition switch to LOCK (0).
16. 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 17.
NO -
Go to the symptom troubleshooting for TPMS indicator does not go off, and no DTCs are stored TPMS Indicator Does Not Go Off, And No DTCs Are Stored.�
17. Do the gauge self-diagnostic function Initial Inspection and Diagnostic Overview.
18. Check for B-CAN system DTCs without the HDS Reading and Clearing Diagnostic Trouble Codes.
Are any B-CAN DTCs indicated?
YES -
Go to the indicated DTC's troubleshooting.�
NO -
Go to step 19.
19. Turn the ignition switch to LOCK (0), then do the 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 connectors, one at a time:
- SRS unit connector A (28P)
- ABS modulator-control unit 25P connector (without VSA)
- VSA modulator-control unit 37P connector (with VSA)
- EPS control unit connector D (28P)
- Immobilizer-keyless control unit 7P connector
- TPMS control unit 20P connector (with TPMS)
- Audio unit 17P connector
- Under-dash fuse/relay box connector Q (16P)
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 (K-line) and the ABS modulator-control unit (without VSA), the VSA modulator-control unit (with VSA), the SRS unit, the EPS control unit, the immobilizer-keyless control unit, the TPMS control unit (with TPMS), the audio 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 the body ground and each of the terminals in the chart?
YES -
Replace the part that does not communicate with the HDS.�
NO -
Repair open in the wire between the DLC (K-line) and the appropriate connector.�
25. Do the gauge self-diagnostic function Initial Inspection and Diagnostic Overview.
26. Check for B-CAN system DTCs without the HDS Reading and Clearing Diagnostic Trouble Codes.
Is DTC B1168, B1169, and/or B1178 indicated?
YES -
Go to step 37.
NO -
Go to step 27.
27. Turn the ignition switch to LOCK (0).
28. Disconnect the HDS from the DLC.
29. Measure the voltage between DLC terminal No. 16 and body ground.
Is there battery voltage?
YES -
Go to step 30.
NO -
Repair open in the wire between DLC terminal No. 16 and the No. 23 BACK UP (10 A) fuse in the under-hood fuse/relay box.�
30. Measure the voltage between DLC terminals No. 4 and No. 16.
Is there battery voltage?
YES -
Go to step 31.
NO -
Repair open in the wire between DLC terminal No. 4 and body ground (G502).�
31. Connect the HDS to the DLC.
32. Jump the SCS line with the HDS.
33. Disconnect ECM connector A (44P).
34. Disconnect the HDS from the DLC.
35. Check for continuity between ECM connector terminal A36 and DLC terminal No. 6.
Is there continuity?
YES -
Go to step 36.
NO -
Repair open in the wire between DLC terminal No. 6 and the ECM (A36).�
36. Check for continuity between ECM connector terminal A37 and DLC terminal No. 14.
Is there continuity?
YES -
Reconnect all connectors, then update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away and the ECM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM was substituted, replace the original ECM Service and Repair.�
NO -
Repair open in the wire between DLC terminal No. 14 and the ECM (A37).�
37. Try to start the engine.
Does the engine start and idle smoothly?
YES -
Go to the F-CAN circuit troubleshooting F-CAN Circuit Troubleshooting.�
NO -
Go to step 38.
38. Turn the ignition switch to LOCK (0).
39. Check the No. 2 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. 2 IG MAIN (50 A) fuse and the ignition switch. If the wire is OK, go to step 40.
NO -
Repair short in the wire between the No. 2 IG MAIN (50 A) fuse and the under-hood fuse/relay box. Also replace the No. 2 IG MAIN (50 A) fuse.�
40. Inspect the No. 19 FI MAIN (15 A) fuse in the under-hood fuse/relay box.
Is the fuse OK?
YES -
Go to step 47.
NO -
Go to step 41.
41. Remove the blown No. 19 FI MAIN (15 A) fuse from the under-hood fuse/relay box.
42. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
43. Check for continuity between body ground and PGM-FI main relay 1 4P connector terminals No. 1 and No. 3 individually.
Is there continuity?
YES -
Replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation. Also replace the No. 19 FI MAIN (15 A) fuse.�
NO -
Go to step 44.
44. Disconnect each of the components or connectors from these components, one at a time, and check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
- PGM-FI main relay 2 (FUEL PUMP)
- ECM connector A (44P)
- Each injector 2P connector
- Camshaft position (CMP) sensor B 3P connector
- Crankshaft position (CKP) sensor 3P connector
- Electronic throttle control system (ETCS) control relay
Does continuity go away when one of the above components is disconnected?
YES -
Replace the part that made the short to body ground go away when disconnected. If the connector that made the short go away is ECM connector A (44P), reconnect all connectors, then update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away and the ECM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM was substituted, replace the original ECM Service and Repair. Also replace the No. 19 FI MAIN (15 A) fuse.�
NO -
Go to step 45.
45. Disconnect the connectors from these parts:
- PGM-FI main relay 2 (FUEL PUMP)
- ECM connector A (44P)
- Injectors
- Camshaft position (CMP) sensor B
- Crankshaft position (CKP) sensor
- Electronic throttle control system (ETCS) control relay
46. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and body ground.
Is there continuity?
YES -
Repair short in the wire between PGM-FI main relay 1 and each item. Also replace the No. 19 FI MAIN (15 A) fuse.�
NO -
Replace PGM-FI main relay 1. Also replace the No. 19 FI MAIN (15 A) fuse.�
47. Inspect the No. 2 FUEL PUMP (15 A) fuse in the under-dash fuse/relay box.
Is the fuse OK?
YES -
Go to step 58.
NO -
Go to step 48.
48. Remove the blown No. 2 FUEL PUMP (15 A) fuse from the under-dash fuse/relay box.
49. Remove PGM-FI main relay 2 (FUEL PUMP) (A) from the under-dash fuse/relay box.
50. Test PGM-FI main relay 2 (FUEL PUMP) Testing and Inspection.
Is the relay OK?
YES -
Go to step 51.
NO -
Replace PGM-FI main relay 2 (FUEL PUMP). Also replace the No. 2 FUEL PUMP (15 A) fuse.�
51. Check for continuity between PGM-FI main relay 2 (FUEL PUMP) 4P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Go to step 52.
NO -
Go to step 54.
52. Jump the SCS line with the HDS, then disconnect ECM connector C (44P).
53. Check for continuity between ECM connector terminal C36 and body ground.
Is there continuity?
YES -
Repair short in the wire between the No. 2 FUEL PUMP (15 A) fuse and the ECM (C36), between the No. 2 FUEL PUMP (15 A) fuse and PGM-FI main relay 2 (FUEL PUMP), or between the No. 2 FUEL PUMP (15 A) fuse and the immobilizer control unit. Also replace the No. 2 FUEL PUMP (15 A) fuse.�
NO -
Replace the No. 2 FUEL PUMP (15 A) fuse, then update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away and the ECM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM was substituted, replace the original ECM Service and Repair.�
54. Remove the rear cushion seat.
55. Remove the rear floor upper cross-member and the access panel from the floor.
56. Disconnect the fuel pump 4P connector.
57. Check for continuity between fuel pump 4P connector terminal No. 2 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. 2 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. 2 FUEL PUMP(15 A) fuse.�
58. Jump the SCS line with the HDS.
59. Disconnect ECM connectors A (44P) and C (44P).
60. Turn the ignition switch to ON (II).
61. Measure the voltage between ECM connector terminal C36 and body ground.
Is there battery voltage?
YES -
Go to step 62.
NO -
Repair open in the wire between the No. 2 FUEL PUMP (15 A) fuse and the ECM (C36).�
62. Measure the voltage between ECM connector terminal A6 and body ground.
Is there battery voltage?
YES -
Go to step 67.
NO -
Go to step 63.
63. Turn the ignition switch to LOCK (0).
64. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
65. 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 66.
NO -
Replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.�
66. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 4 and ECM connector terminal A6.
Is there continuity?
YES -
Test PGM-FI main relay 1 Testing and Inspection. If the relay is OK, update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away and the ECM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM was substituted, replace the original ECM Service and Repair.�
NO -
Repair open in the wire between the ECM (A6) and PGM-FI main relay 1.�
67. Turn the ignition switch to LOCK (0).
68. Remove PGM-FI main relay 1 (C) from the under-hood fuse/relay box.
69. Measure the voltage between PGM-FI main relay 1 4P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
Go to step 70.
NO -
Replace the under-hood fuse/relay box Under-Hood Fuse/Relay Box Removal and Installation.�
70. Check for continuity between PGM-FI main relay 1 4P connector terminal No. 2 and ECM connector terminal A8.
Is there continuity?
YES -
Go to step 71.
NO -
Repair open in the wire between the ECM (A8) and PGM-FI main relay 1.�
71. Test PGM-FI main relay 1 Testing and Inspection.
Is PGM-FI main relay 1 OK?
YES -
Go to step 72.
NO -
Replace PGM-FI main relay 1.�
72. Disconnect ECM connector B (44P).
73. Check for continuity between body ground and ECM connector terminals B1, B36, C2, C40, and C44 individually.
Is there continuity?
YES -
Go to step 74.
NO -
Repair open in the wire between the ECM (B1, B36, C2, C40, C44) and G101 Connector And Harness Locations.�
74. Check for continuity between ECM connector terminal C13 and body ground.
Is there continuity?
YES -
Go to step 75.
NO -
Go to step 76.
75. Continue to check for continuity between ECM connector terminal C13 and body ground, while disconnecting the MAP sensor 3P connector.
Is there continuity?
YES -
Repair short in the wire between the ECM (C13) and the MAP sensor.�
NO -
Replace the MAP sensor Service and Repair.�
76. Check for continuity between ECM connector terminal B18 and body ground.
Is there continuity?
YES -
Go to step 77.
NO -
Go to step 78.
77. Continue to check for continuity between ECM connector terminal B18 and body ground, while disconnecting the output shaft (countershaft) speed sensor 3P connector.
Is there continuity?
YES -
Repair short in the wire between the ECM (B18) and the output shaft (countershaft) speed sensor.�
NO -
Replace the output shaft (countershaft) speed sensor Service and Repair.�
78. Check for continuity between ECM connector terminal C12 and body ground.
Is there continuity?
YES -
Go to step 79.
NO -
Go to step 80.
79. Continue to check for continuity between ECM connector terminal C12 and body ground, while disconnecting the throttle body 6P connector.
Is there continuity?
YES -
Repair short in the wire between the ECM (C12) and the throttle body.�
NO -
Replace the throttle body Removal and Replacement.�
80. Check for continuity between ECM connector terminal A25 and body ground.
Is there continuity?
YES -
Go to step 81.
NO -
Go to step 82.
81. Continue to check for continuity between ECM connector terminal A25 and body ground, while disconnecting the APP sensor 6P connector.
Is there continuity?
YES -
Repair short in the wire between the ECM (A25) and the APP sensor.�
NO -
Replace the accelerator pedal module; '06-08 models, '09-11 models Service and Repair.�
82. Check for continuity between ECM connector terminal A24 and body ground.
Is there continuity?
YES -
Go to step 83.
NO -
Go to step 84.
83. Continue to check for continuity between ECM connector terminal A24 and body ground, while disconnecting the APP sensor 6P connector.
Is there continuity?
YES -
Repair short in the wire between the ECM (A24) and the APP sensor.�
NO -
Replace the accelerator pedal module; '06-08 models, '09-11 models Service and Repair.�
84. Check for continuity between ECM connector terminal A19 and body ground.
Is there continuity?
YES -
Go to step 85.
NO -
Reconnect all connectors, then update the ECM if it does not have the latest software ECM/PCM Update, or substitute a known-good ECM, then recheck. If the symptom/indication goes away and the ECM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM was substituted, replace the original ECM Service and Repair.�
85. Continue to check for continuity between ECM connector terminal A19 and body ground, while disconnecting these connectors, one at a time:
- A/C pressure sensor 3P connector
- FTP sensor 3P connector
Does continuity go away when one of the above connectors is disconnected?
YES -
Replace the part that caused an open when it was disconnected.�
NO -
Repair short in the wire between the ECM (A19) and the A/C pressure sensor or the FTP sensor.�