Front Blower Motor Inoperative (ATC)
*FRONT BLOWER MOTOR INOPERATIVE (ATC)
For a complete wiring diagram Consult Diagrams/Electrical
Diagnostic Test
1. CHECK FOR IPM DTCs
NOTE: Verify that the vehicle's odometer displays more than 3 miles. If not, drive the vehicle until the odometer displays more than 3 miles. Then, check blower motor operation and if still inoperative proceed as follows:
Turn the ignition on.
With the scan tool, read IPM DTCs.
Does the scan tool display any DTCs?
Yes
- Diagnose and Repair the DTC(s).
No
- Go To 2
2. CHECK IPM FUSE #42 (FRONT BLOWER FUSE)
Turn the ignition off.
Remove and inspect IPM Fuse #42 (Front Blower Fuse).
Is the fuse open?
Yes
- Replace the fuse. Then, Go To 3
No
- Reinstall the fuse. Then, Go To 6
3. CHECK FRONT BLOWER OPERATION
Turn the ignition on.
Operate the Front Blower Motor in all speeds.
Start the engine and operate the A/C Heater Control in all modes and speeds.
Does the Front Blower Motor operate properly without blowing the fuse?
Yes
- Refer to Diagrams/Electrical to help isolate a possible intermittent short to ground condition.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 4
4. CHECK (C7) FUSED FRONT BLOWER RELAY OUTPUT CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off.
Disconnect the Front Blower Power Module C1 harness connector.
Measure the resistance between ground and the (C7) Fused Front Blower Relay Output circuit.
Does the ohm meter read open circuit?
Yes
- Replace IPM Fuse #42 (Front Blower Fuse). Then, Go To 5
No
- Repair the (C7) Fused Front Blower Relay Output circuit for a short to ground.
- Replace IPM Fuse #42 (Front Blower Fuse).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
5. CHECK FRONT BLOWER MOTOR OPERATION WITH FRONT BLOWER POWER MODULE BYPASSED
Disconnect the Front Blower Power Module C2 harness connector.
Connect a jumper wire between the (C7) Fused Front Blower Relay Output circuit in the Front Blower Power Module C1 harness connector and the (C112) Blower Motor Supply circuit in the Front Blower Power Module C2 harness connector.
Connect a jumper wire between the (Z134) Ground circuit in the Front Blower Power Module C1 harness connector and the (C113) Blower Motor Ground circuit in the Front Blower Power Module C2 harness connector.
Turn the ignition on.
Does the Front Blower Motor operate at full speed without blowing the fuse?
Yes
- Replace the Front Blower Power Module.
- Replace IPM Fuse #42 (Front Blower Fuse).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Replace the Front Blower Motor.
- Replace IPM Fuse #42 (Front Blower Fuse).
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
6. CHECK FOR POWER TO FRONT BLOWER POWER MODULE
Disconnect the Front Blower Power Module C1 harness connector.
Turn the ignition on.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Using a 12-volt test light connected to ground, back probe the (C7) Fused Front Blower Relay Output circuit in the Front Blower Power Module C1 harness connector.
Does the test light illuminate brightly?
Yes
- Go To 7
No
- Go To 13
7. CHECK (Z134) GROUND CIRCUIT FOR AN OPEN
Turn the ignition off.
Measure the resistance between ground and the (Z134) Ground circuit in the Front Blower Power Module C1 harness connector.
Does the ohm meter read open circuit?
Yes
- Repair the (Z134) Ground circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 8
8. CHECK (C56) FRONT BLOWER MOTOR CONTROL CIRCUIT FOR A SHORT TO VOLTAGE
Disconnect the A/C Heater Control harness connector.
Turn the ignition on.
Measure the voltage of the (C56) Front Blower Motor Control circuit.
Is the voltage above 0.2 volts?
Yes
- Repair the (C56) Front Blower Motor Control circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 9
9. CHECK (C56) FRONT BLOWER MOTOR CONTROL CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the (C56) Front Blower Motor Control circuit between the Front Blower Power Module C1 harness connector and the A/C Heater Control harness connector.
Does the ohm meter read open circuit?
Yes
- Repair the (C56) Front Blower Motor Control circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 10
10. CHECK (C56) FRONT BLOWER MOTOR CONTROL CIRCUIT VOLTAGE
Reconnect the Front Blower Power Module C1 harness connector.
Reconnect the A/C Heater Control harness connector.
Start the engine.
Press the A/C Heater Control's PWR switch on.
Set the front blower speed to low.
While back probing, measure the voltage of the (C56) Front Blower Motor Control circuit in the A/C Heater Control harness connector.
Is the voltage above 7.5 volts?
Yes
- Go To 11
No
- Replace the Front Blower Power Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
11. CHECK FRONT BLOWER MOTOR OPERATION WITH A/C HEATER CONTROL BYPASSED
Turn the ignition off.
Disconnect the A/C Heater Control harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground, back probe the (C56) Front Blower Control circuit in the A/C Heater Control harness connector.
Does the Front Blower Motor run at high speed?
Yes
- Replace the A/C Heater Control.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Go To 12
12. CHECK FRONT BLOWER MOTOR OPERATION WITH FRONT BLOWER POWER MODULE BYPASSED
Turn the ignition off.
Reconnect the A/C Heater Control harness connector.
Disconnect the Front Blower Power Module C1 harness connector.
Disconnect the Front Blower Power Module C2 harness connector.
Connect a jumper wire between the (C7) Fused Front Blower Relay Output circuit in the Front Blower Power Module C1 harness connector and the Blower Motor Supply circuit in the Front Blower Power Module C2 harness connector.
Connect a jumper wire between the (Z134) Ground circuit in the Front Blower Power Module C1 harness connector and the Blower Motor Ground circuit in the Front Blower Power Module C2 harness connector.
Turn the ignition on.
Does the Front Blower Motor operate at full speed?
Yes
- Replace the Front Blower Power Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Replace the Front Blower Motor.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
13. CHECK IPM FOR AN OPEN CIRCUIT TO FRONT BLOWER RELAY CAVITY 30
Turn the ignition off.
Remove the Front Blower Relay from the IPM.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Using a 12-volt test light connected to ground, probe cavity 30 of the Front Blower Relay connector.
Does the test light illuminate brightly?
Yes
- Go To 14
No
- Replace the IPM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
14. CHECK (C7) FUSED FRONT BLOWER MOTOR RELAY OUTPUT CIRCUIT FOR AN OPEN TO IPM FUSE #42
Remove IPM Fuse #42 (Front Blower Fuse).
Measure the resistance between cavity 87 of the Front Blower Relay connector and IPM Fuse #42 (power input cavity).
Is the resistance below 5.0 ohms?
Yes
- Go To 15
No
- Replace the IPM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
15. CHECK FRONT BLOWER RELAY
Install the Front Blower Relay.
Turn the ignition on.
NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
Using a 12-volt test light connected to ground, probe IPM Fuse #42 (power input cavity).
Does the test light illuminate brightly?
Yes
- Go To 16
No
- Replace the Front Blower Relay.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
16. CHECK (C7) FUSED FRONT BLOWER MOTOR RELAY OUTPUT CIRCUIT FOR AN OPEN
Turn the ignition off.
Disconnect the IPM C9 harness connector.
Measure the resistance between IPM Fuse #42 (power output cavity) and cavity 8 of the IPM C9 connector (IPM side).
Does the ohm meter read open circuit?
Yes
- Replace the IPM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.
No
- Repair the (C7) Fused Front Blower Relay Output circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.