DLC Circuit Troubleshooting

NOTE:

If the ECM/PCM does not communicate with the Honda PGM Tester or HDS, do this troubleshooting procedure.
Check that MIL circuit is normal, then do this troubleshooting.

Measure voltage between DLC terminal No. 16 and body ground.

DATA LINK CONNECTOR (DLC)Terminal side of female terminals+B
(WHT/GRN)

Is there battery voltage?

YES - Go to 2.

NO - Repair open in the wire between DLC terminal No. 16 and the No. 8 FI ECU (ECM/PCM) (15A) fuse in the under-hood fuse/relay box.n

2.	Measure voltage between DLC terminals No. 4 and No. 16. DATA LINK CONNECTOR (DLC)GND (BLK)+B (WHT/GRN)Terminal side of female terminals Is there battery voltage? YES - Go to 3. NO - Repair open in the wire between DLC terminal No. 4 and body ground (G451).n

3.	Measure voltage between DLC terminals No. 5 and No. 16. DATA LINK CONNECTOR (DLC)LG3 (BLK)+B (WHT/GRN)Terminal side of female terminals Is there battery voltage? YES - Go to 4. NO - Repair open in the wire between the ECM/PCM (E3) and DLC terminal No. 5.n

4.	Turn the ignition switch ON (II).

5.	Measure voltage between DLC terminals No. 5 and No. 7. DATA LINK CONNECTOR (DLC)K-LINE (LT BLU)Terminal side of female terminalsLG3 (BLK) Is there 8.5 V or more? YES - Go to 11. NO - Go to 6.

6.	Turn the ignition switch OFF.

7.	Jump the SCS line with the Honda PGM Tester or the HDS.

8.	Disconnect ECM/PCM connector E (31P).

Check for continuity between DLC terminal No. 7 and body ground.

DATA LINK CONNECTOR (DLC)K-LINE
(LT BLU)Terminal side of female terminals

Is there continuity?

YES - Repair short to ground in the wire between DLC terminal No. 7 and the ECM/PCM (E23). After repairing the wire, check for a DTC with the Honda PGM Tester or the HDS and go to the DTC Troubleshooting index.n

NO - Go to 10.

10.

Check for continuity between DLC terminal No. 7 and ECM/PCM terminal E23.

ECM/PCM CONNECTOR E (31P)DATA LINK CONNECTOR (DLC)Wire side of
female terminalsTerminal side of female terminalsK-LINE (LT BLU)K-LINE
(LT BLU)

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.n

NO - Repair open in the wire between DLC terminal No. 7 and the ECM/PCM (E23). After repairing the wire, check for a DTC with the Honda PGM Tester or the HDS and go to the DTC Troubleshooting index.n

11.	Turn the ignition switch OFF.

12.	Jump the SCS line with the Honda PGM Tester or the HDS.

13.	Disconnect ECM/PCM connector E (31P).

14.	Turn the ignition switch ON (II).

15.

Measure voltage between DLC terminals No. 5 and No. 7.

DATA LINK CONNECTOR (DLC)K-LINE
(LT BLU)LG3 (BLK)Terminal side of female terminals

Is there 0 V?

NO - Repair short to power in the wire between DLC terminal No. 7 and the ECM/PCM (E23). After repairing the wire, check for a DTC with the Honda PGM Tester or the HDS, and go to the DTC Troubleshooting index.n