DLC Circuit Troubleshooting
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.
HDS communication check:

HDS communication check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Connect the HDS to the DLC.
NOTE: Make sure the HDS is properly connected to the DLC.

?3.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and turn on the HDS.

Does the HDS identify the vehicle?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Go to step 13.
2.
Determine possible failure area (PGM-FI system, other systems):

Determine possible failure area (PGM-FI system, other systems)
?1.
Check for Pending or Confirmed DTCs in the PGM-FI system with the HDS.
DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
       

Are any Pending or Confirmed DTCs indicated?

     
YES
     
     
     
Go to the indicated DTC's troubleshooting.?
     
NO
     
     
     
If the HDS does not communicate with the VSA system, go to step 3.
     
NO
     
     
     
If the HDS does not communicate with the SRS, go to step 4.
     
NO
     
     
     
If the HDS does not communicate with the EPS system, go to step 5.
     
NO
     
     
     
If the HDS does not communicate with the IMMOBI (immobilizer) system, go to step 6.
     
NO
     
     
     
If the HDS does not communicate with the keyless access system, go to step 7.
     
NO
     
     
     
If the HDS does not communicate with the BODY ELECTRICAL system, go to step 8.
     
NO
     
     
     
If the HDS does not communicate with the DRIVING SUPPORT system, go to step 9.
3.
VSA system check:

VSA system check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and watch the VSA indicator.

Does the VSA indicator come on and go off?

     
YES
     
     
     
The VSA system is OK. Go to step 10.
     
NO
     
     
     
4.
SRS check:

SRS check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and watch the SRS indicator.

Does the SRS indicator come on and go off?

     
YES
     
     
     
The SRS is OK. Go to step 10.
     
NO
     
     
     
5.
EPS system check:

EPS system check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Start the engine, and watch the EPS indicator.

Does the EPS indicator come on and go off?

     
YES
     
     
     
The EPS system is OK. Go to step 10.
     
NO
     
     
     
6.
Immobilizer system check:

Immobilizer system check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and watch the immobilizer indicator.

Does the immobilizer indicator stay on or flash?

     
YES
     
     
     
Go to the immobilizer system troubleshooting.?
     
NO
     
     
     
The immobilizer system is OK. Go to step 10.
7.
Keyless access system check:

Keyless access system check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and watch the keyless access indicator.

Does the keyless access indicator stay on?

     
YES
     
     
     
     
NO
     
     
     
The keyless access system is OK. Go to step 10.
8.
Body electrical system check:

Body electrical system check
?1.

?2.
Check the gauge display.

Is Error 2 indicated?

     
YES
     
     
     
Go to the indicated DTC's troubleshooting.?
     
NO
     
     
     
The body electrical system is OK. Go to step 10.
9.
Driving support system check:

Driving support system check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, and watch the ACC, CMBS, LKAS, and/or RDM indicators.

Do these indicators stay on?

     
YES
     
     
     
Go to the symptom troubleshooting for the ACC, CMBS, LKAS, and/or RDM indicators do not go off.?
     
NO
     
     
     
The driving support system is OK. Go to step 10.
10.
Open wire check (K LINE line or L-LINE line):

Open wire check (K LINE line or L-LINE line)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the HDS from the DLC.

?3.
Disconnect the control unit(s) on the K LINE that does not communicate.
NOTE: Before disconnecting the SRS unit connector, do the battery terminal disconnection procedure and wait for at least 3 minutes.



?4.
Check for continuity between DLC (16P) No. 7 (LT BLU) and the disconnected connector terminal(s):
Connector
Terminal
EPS control unit connector A (11P)
No. 7 (LT BLU)
Audio-navigation unit connector A (24P) (with navigation)
No. 13 (LT BLU)
Audio unit connector A (24P) (without navigation)
No. 13 (LT BLU)
ANC/active sound control unit 20P connector
No. 14 (LT BLU)
Immobilizer-keyless control unit 7P connector (without keyless access system)
No. 3 (LT BLU)
Keyless access control unit connector B (28P) (with keyless access system)
No. 20 (LT BLU)
Under-dash fuse/relay box connector R (16P)
No. 12 (LT BLU)

L-LINE
Connector
Terminal
SRS unit connector A (39P)
No. 33 (YEL)
Keyless access control unit connector C (24P)
No. 3 (YEL)

Is there continuity between the DLC and the terminals in the chart?

     
YES
     
     
     
Go to step 11.
     
NO
     
     
     
Repair an open in the wire between the DLC (K LINE wire or L-LINE wire) and the appropriate connector.?
11.
Determine possible failure area (short in K LINE line or L-LINE line, others):

Determine possible failure area (short in K LINE line or L-LINE line, others)
?1.
Reconnect all connectors.

?2.
If the battery negative terminal is disconnected in step 10-3, do the battery terminal reconnection procedure.

?3.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Test condition
IG ON (II) or ON mode
Test circuit
K LINE and L-LINE
Test point 1
DLC (16P) No. 7 (LT BLU) and No. 15 (YEL)
Test point 2
Body ground


Is there any voltage?

     
YES
     
     
     
Go to step 13.
     
NO
     
     
     
Go to step 12.
12.
Shorted wire check (K LINE line, L-LINE line):

Shorted wire check (K LINE line, L-LINE line)
?1.
Continue to measure the voltage between DLC (16P) terminal No. 7 (K LINE line) and body ground, or DLC (16P) terminal No. 15 (L-LINE line) and body ground while disconnecting these parts, one at a time:
NOTE: Turn the ignition switch to LOCK (0) or press the engine start/stop button to select the OFF mode before disconnecting the connector, and turn the ignition switch to ON (II) or press the engine start/stop button to select the ON mode before measuring the voltage.


L-LINE
NOTE: Before disconnecting the SRS unit connector, do the battery terminal disconnection procedure and wait for at least 3 minutes.

Does voltage come back when one of the above components is disconnected?

     
YES
     
     
     
Replace the part that any voltage was detected when it was disconnected.?
     
NO
     
     
     
Repair a short in the wire between DLC (16P) terminal No. 7 (K LINE) and the EPS control unit, the audio unit (without navigation), the audio-navigation unit (with navigation), the under-dash fuse/relay box (MICU), the ANC/active sound control unit, the immobilizer-keyless control unit (without keyless access system), or the keyless access control unit (with keyless access system), or repair a short in the wire between DLC (16P) terminal No. 15 (L-LINE) and the SRS unit or the keyless access control unit (with keyless access system).?
13.
Body electrical system (B-CAN) check:

Body electrical system (B-CAN) check
?1.

?2.
Check for gauge control module DTCs without the HDS.

Is DTC U0029 and/or U0100 indicated?

     
YES
     
     
     
     
NO
     
     
     
Go to step 14.
14.
Open wire check (+B BACK UP line):

Open wire check (+B BACK UP line)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the HDS from the DLC.

?3.
Measure the voltage between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
Test circuit
+B BACK UP
Test point 1
DLC (16P) No. 16 (WHT)
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The +B BACK UP wire is OK. Go to step 15.
     
NO
     
     
     
Repair an open in the +B BACK UP wire between DLC (16P) terminal No. 16 and the No. A21 (10 A) fuse in the under-hood fuse/relay box.?
15.
Open wire check (GND line):

Open wire check (GND line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
Test circuit
GND, +B BACK UP
Test point 1
DLC (16P) No. 4 (BLK)
Test point 2
DLC (16P) No. 16 (WHT)


Is there battery voltage?

     
YES
     
     
     
The GND wire is OK. Go to step 16.
     
NO
     
     
     
Repair an open in the GND wire between DLC (16P) terminal No. 4 and G501.?
16.
Open wire check (F-CAN_H line):

Open wire check (F-CAN_H line)
?1.
Connect the HDS to the DLC.

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
PCM connector A (51P): disconnected
Test circuit
F-CAN_H
Test point 1
DLC (16P) No. 6 (WHT)
Test point 2
PCM connector A (51P) No. 2 (WHT)


Is there continuity?

     
YES
     
     
     
The F-CAN_H wire is OK. Go to step 17.
     
NO
     
     
     
Repair an open in the F-CAN_H wire between the PCM (A2) and DLC (16P) terminal No. 6.?
17.
Open wire check (F-CAN_L line):

Open wire check (F-CAN_L line)
?1.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
PCM connector A (51P): disconnected
Test circuit
F-CAN_L
Test point 1
DLC (16P) No. 14 (RED)
Test point 2
PCM connector A (51P) No. 1 (RED)


Is there continuity?

     
YES
     
     
     
The F-CAN_L wire is OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good PCM.?
     
NO
     
     
     
Repair an open in the F-CAN_L wire between the PCM (A1) and DLC (16P) terminal No. 14.?