DLC Circuit Troubleshooting

NOTE:


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

 

Is there battery voltage?


YES - Go to 2.


NO - Repair open in the wire between DLC terminal No. 16 and the No. 9 BACK UP (10 A) fuse in the under-hood fuse/relay box.n


2.Measure voltage between DLC terminals No. 4 and No. 16.

 

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.

 

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.

 

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 HDS.

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

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

 

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 HDS, and go to the indicated DTC's troubleshooting.n


NO - Go to 10.


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

 

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 HDS, and go to the indicated DTC's troubleshooting.n


11.Turn the ignition switch OFF.

12.Jump the SCS line with 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.

 

Is there 0 V?


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 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 HDS, and go to the indicated DTC's troubleshooting.n