B1235

Control System DTCs

DTC Troubleshooting: B1235 - (42)

DTC B1235 or DTC indicator 42 : A Problem in the Air Mix Control Motor Circuit, Linkage, Door, or Motor (Driver's)


1. Problem verification:

-1. Clear the DTCs with the HDS.

-2. Turn the ignition switch to LOCK (0), and then back to ON (II).

-3. Do the Self-Diagnostic Function with the HDS or the climate control unit How to Troubleshoot the Climate Control System.

-4. Check for DTCs.





Is DTC B1235 or 42 indicated?
-YES- Go to step 2.
-NO- Intermittent failure. Check for loose wires or poor connections in the driver's air mix control motor circuit.

2. Open wire check (M-HOT DR/M-HOT, M-COOL DR/M-COOL lines):

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

-2. Disconnect the following connectors.





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














Is there continuity?
-YES- The M-HOT DR/M-HOT and M-COOL DR/M-COOL wires are not open. Go to step 3.
-NO- Repair an open in the wire(s) between the climate control unit and the driver's air mix control motor.

3. Shorted wire check (M-HOT DR, M-COOL DR lines):

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














Is there continuity?
-YES- Repair a short to body ground in the wire(s) between the climate control unit and the driver's air mix control motor.
-NO- The M-HOT and M-COOL wires are OK. Go to step 4.

4. Driver's air mix control motor check:

-1. Test the driver's air mix control motor Drivers Air Mix Control Motor Test (Climate Control).

Is the driver's air mix control motor OK?
-YES- Replace the climate control unit Climate Control Unit Removal And Installation (Climate Control).
-NO- Replace the driver's air mix control motor Drivers Air Mix Control Motor Removal And Installation (Climate Control), or repair the air mix control linkage or door.