DLC Circuit Troubleshooting

NOTE:

If the PCM does not communicate with the HDS, or I/M test equipment, do this troubleshooting procedure.
Check that MIL circuit is normal, then do this troubleshooting.

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

Fig 1: Measuring Voltage Between DLC Terminal 16 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Go to step 2.
2. NO - Repair open in the wire between DLC terminal No. 16 and the No. 46 ACGS (15 A) fuse in the under-hood fuse/relay box.
Measure voltage between DLC terminals No. 4 and No. 16.

Fig 2: Measuring Voltage Between DLC Terminals 4 And 16
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Go to step 3.
2. NO - Repair open in the wire between DLC terminal No. 4 and body ground (G401).
Measure voltage between DLC terminals No. 5 and No. 16.

Fig 3: Measuring Voltage Between DLC Terminals 5 And 16
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there battery voltage?
1. YES - Go to step 4.
2. NO - Repair open in the wire between DLC terminal No. 5 and body ground (G101).
Turn the ignition switch ON (II).
Measure voltage between DLC terminals No. 5 and No. 7.

Fig 4: Measuring Voltage Between DLC Terminals 5 And 7
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there 8.5 V or more?
1. YES - Go to step 12.
2. NO - Go to step 6.
Turn the ignition switch OFF.
Jump the SCS line with the HDS.
Disconnect PCM connector B (56P).
Check for continuity between DLC terminal No. 7 and body ground.

Fig 5: Checking Continuity Between DLC Terminal 7 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Repair short to ground in the wire between DLC terminal No. 7 and the PCM (B17). After repairing the wire, check for a DTC with the HDS, and go to the indicated DTC's troubleshooting.
2. NO - Go to step 10.
Connect DLC terminal No. 7 to body ground with a jumper wire.

Fig 6: Connecting DLC Terminal 7 To Body Ground With Jumper Wire
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Check for continuity between PCM connector terminal B17 and body ground.

Fig 7: Checking Continuity Between PCM Connector Terminal B17 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?
1. YES - Update the PCM if it does not have the latest software, or substitute a known-good PCM (see PCM UPDATING AND SUBSTITUTION FOR TESTING ), then recheck. If the symptom/ indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
2. NO - Repair open in the wire between DLC terminal No. 7 and the PCM (B17). After repairing the wire, check for a DTC with the HDS, and go to the indicated DTC's troubleshooting.
Turn the ignition switch OFF.
Jump the SCS line with the HDS.
Disconnect PCM connector B (56P).
Turn the ignition switch ON (II).
Measure voltage between DLC terminals No. 4 and No. 7.

Fig 8: Measuring Voltage Between DLC Terminals 4 And 7
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there 0V?
1. YES - Update the PCM if it does not have the latest software, or substitute a known-good PCM (see page 11-6), then recheck. If the symptom/ indication goes away with a known-good PCM, replace the original PCM (see PCM REPLACEMENT ).
2. NO - Repair short to power in the wire between DLC terminal No. 7 and the PCM (B17). After repairing the wire, check for a DTC with the HDS, and go to the indicated DTC's troubleshooting.