HVAC Control Unit

Control System DTCs

HVAC DTC Troubleshooting: 5

DTC indicator 5 : A Short in the Mode Control Motor Circuit

1. Problem verification:

Problem verification
-1. Turn the ignition switch to LOCK (0), and then back to ON (II).

-2. Do the Self-Diagnostic Function with the HVAC control unit How to Troubleshoot the Heating and A/C Systems (Manual A/C).

-3. Check for DTCs.

Is DTC 5 indicated?
-YES- Go to step 2.
-NO- Intermittent failure. Check for loose wires or poor connections on the mode control motor circuit.

2. DTC check:

DTC check
-1. Turn the ignition switch to LOCK (0).

-2. Disconnect the following connector.





-3. Turn the ignition switch to ON (II).

-4. Do the Self-Diagnostic Function with the HVAC control unit How to Troubleshoot the Heating and A/C Systems (Manual A/C).

-5. Check for DTCs.

Is DTC 5 indicated?
-YES- Go to step 3.
-NO- Replace the mode control motor Mode Control Motor Removal and Installation.

3. Mode control motor S5V line check:

Mode control motor S5V line check
-1. Measure the voltage between test points 1 and 2.









Is there 5 V?
-YES- Go to step 4.
-NO- Go to step 5.

4. Shorted wire check (MDD-P line):

Shorted wire check (MDD-P line)
-1. Turn the ignition switch to LOCK (0).

-2. Disconnect the following connector.





-3. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- Repair a short in the wire between the HVAC control unit and the mode control motor.
-NO- The MDD-P wire is OK. Replace the HVAC control unit HVAC Control Unit Removal and Installation (With Navigation).

5. Shorted wire check (S_5V line):

Shorted wire check (S_5V line)
-1. Turn the ignition switch to LOCK (0).

-2. Disconnect the following connector.





-3. Check for continuity between test points 1 and 2.









Is there continuity?
-YES- Repair a short in the wire between the HVAC control unit and the mode control motor.
-NO- The S_5V wire is OK. Replace the HVAC control unit HVAC Control Unit Removal and Installation (With Navigation).