Blower Motor Inoperative (Except SRT10)
BLOWER MOTOR INOPERATIVE (EXCEPT SRT10)Blower Motor Inoperative (Except SRT10):
POSSIBLE CAUSES
- (C7) Blower motor feed circuit shorted to ground
- (A970) Fused B(+) circuit shorted to ground
- (C70) Blower motor high driver circuit open
- (Z134) Ground circuit open
- (C7) Blower motor feed circuit open
- (A970) Fused B(+) circuit open
- IPM fuse #4 open
- Blower motor
- Ignition switch
- A/C heater control
Diagnostic Test
1. CHECK THE FUSE
Turn the ignition off.
Remove and inspect IPM Fuse #4.
Q: Is the fuse open?
YES: Replace IPM Fuse #4 and Go To 2.
NO: Reinstall IPM Fuse #4 and Go To 5.
2. CHECK BLOWER MOTOR OPERATION
Turn the ignition on.
Turn the blower on and operate it in all speeds and modes.
Q: Does the blower motor operate properly without blowing the fuse?
YES: Check the (C7) Blower Motor Feed circuit and the (A970) Fused B(+) circuit for an intermittent short to ground. Repair as necessary. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 3
3. CHECK THE (C7) BLOWER MOTOR FEED CIRCUIT FOR A SHORT TO GROUND
Turn the ignition off.
Disconnect the Blower Motor harness connector.
Measure the resistance of the (C7) Blower Motor Feed circuit between ground and the Blower Motor harness connector.
Q: Is the resistance below 10K ohms?
YES: Repair the (C7) Blower Motor Feed circuit for a short to ground and replace the fuse. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 4
4. CHECK THE (A970) FUSED B(+) CIRCUIT FOR A SHORT TO GROUND
Disconnect the Ignition Switch harness connector.
Measure the resistance of the (A970) Fused B(+) circuit between ground and the Ignition Switch harness connector.
Q: Is the resistance below 10K ohms?
YES: Repair the (A970) Fused B(+) circuit for a short to ground and replace the fuse. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Blower Motor and fuse. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
5. CHECK THE (C7) BLOWER MOTOR FEED CIRCUIT USING A TEST LIGHT
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) Blower Motor Feed circuit in the Blower Motor harness connector.
Q: Does the test light illuminate brightly?
YES: Go To 6
NO: Go To 9
6. CHECK BLOWER MOTOR OPERATION BY BYPASSING THE A/C HEATER CONTROL
Turn the ignition off.
Connect a jumper wire between ground and the (C70) Blower Motor High Driver circuit in the Blower Motor harness connector.
Turn the ignition on.
Q: Does the blower motor run at high speed?
YES: Go To 7
NO: Replace the Blower Motor. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
7. CHECK THE (C70) BLOWER MOTOR HIGH DRIVER CIRCUIT FOR AN OPEN
Turn the ignition off.
Disconnect the A/C Heater Control C2 harness connector.
Disconnect the Blower Motor harness connector.
Measure the resistance of the (C70) Blower Motor High Driver circuit between the A/C Heater Control C2 harness connector and the Blower Motor harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Go To 8
NO: Repair the (C70) Blower Motor High Driver circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
8. CHECK THE (Z134) GROUND CIRCUIT FOR AN OPEN
Measure the resistance of the (Z134) Ground circuit between ground and the A/C Heater Control C2 harness connector.
Q: Is the resistance below 5.0 ohms?
YES: Replace the A/C Heater Control.
NO: Repair the (Z134) Ground circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
9. CHECK THE (C7) BLOWER MOTOR FEED CIRCUIT FOR AN OPEN
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) Blower Motor Feed circuit in the Ignition Switch harness connector.
Q: Does the test light illuminate brightly?
YES: Repair the (C7) Blower Motor Feed circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 10
10. CHECK THE (A970) FUSED B(+) CIRCUIT FOR AN OPEN
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 (A970) Fused B(+) circuit in the Ignition Switch harness connector.
Q: Does the test light illuminate brightly?
YES: Replace the Ignition Switch. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Repair the (A970) Fused B(+) circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test