HVAC DTC Troubleshooting: 6
DTC indicator 6: A Problem in the Mode Control Motor Circuit, Linkage, Door, or Motor
1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

?2.
Do the Self-Diagnostic Function with the HVAC control unit.

?3.
Check for DTCs.

Is DTC 6 indicated?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Intermittent failure. Check for loose wires or poor connections on the mode control motor circuit.?
2.
Open wire check (M-DEF line):

Open wire check (M-DEF line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connectors.
HVAC control unit 32P connector
Mode control motor 7P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HVAC control unit 32P connector : disconnected
 
Mode control motor 7P connector: disconnected
Test point 1
HVAC control unit 32P connector No. 30
Test point 2
Mode control motor 7P connector No. 6


Is there continuity?

     
YES
     
     
     
The M-DEF wire is not open. Go to step 3.
     
NO
     
     
     
Repair an open in the wire between the HVAC control unit and the mode control motor.?
3.
Open wire check (M-VENT line):

Open wire check (M-VENT line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HVAC control unit 32P connector: disconnected
 
Mode control motor 7P connector: disconnected
Test point 1
HVAC control unit 32P connector No. 29
Test point 2
Mode control motor 7P connector No. 7


Is there continuity?

     
YES
     
     
     
The M-VENT wire is not open. Go to step 4.
     
NO
     
     
     
Repair an open in the wire between the HVAC control unit and the mode control motor.?
4.
Shorted wire check (M-DEF line):

Shorted wire check (M-DEF line)
?1.
Check for continuity between test points 1 and 2 individually.
Test condition
Vehicle OFF (LOCK) mode
 
HVAC control unit 32P connector: disconnected
 
Mode control motor 7P connector: disconnected
Test point 1
HVAC control unit 32P connector No. 30
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to ground in the wire between the HVAC control unit and the mode control motor.?
     
NO
     
     
     
The M-DEF wire is OK. Go to step 5.
5.
Shorted wire check (M-VENT line):

Shorted wire check (M-VENT line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
HVAC control unit 32P connector: disconnected
 
Mode control motor 7P connector: disconnected
Test point 1
HVAC control unit 32P connector No. 29
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
Repair a short to ground in the wire between the HVAC control unit and the mode control motor.?
     
NO
     
     
     
The M-VENT wire is OK. Go to step 6.
6.
Mode control motor check:

Mode control motor check
?1.
Test the mode control motor.

Is the mode control motor OK?

     
YES
     
     
     
     
NO
     
     
     
Replace the mode control motor, or repair the mode control linkage or doors.?