Symptom:
*BLOWER MOTOR SPEEDS INCORRECT
POSSIBLE CAUSES
BLOWER MOTOR DRIVER CIRCUIT(S) SHORTED TO GROUND
A/C - HEATER CONTROL MODULE
BLOWER MOTOR DRIVER CIRCUIT(S) SHORTED TO VOLTAGE
BLOWER MOTOR DRIVER CIRCUITS SHORTED TOGETHER
A/C - HEATER CONTROL MODULE - SPEEDS INCORRECT
BLOWER MOTOR DRIVER CIRCUIT(S) OPEN
BLOWER MOTOR RESISTOR BLOCK - OPEN SPEED
TEST
ACTION
APPLICABILITY
1
Turn the Blower control to the Off position.
Turn the ignition on.
Does the blower run?
All
Yes
→ Go To 2
No
→ Go To 3
2
Turn the ignition off.
Disconnect the A/C - Heater Control Module C1 harness connector.
Disconnect the Blower Motor Resistor Block harness connector.
Measure the resistance between ground and each of the Blower Motor Driver circuits.
Is the resistance below 10K ohms on any of the circuits?
All
Yes
→ Repair all Blower Motor Driver circuits with a resistance below
10K ohms for a short to ground.
Perform BODY VERIFICATION TEST - VER 1.
No
→ Replace the A/C - Heater Control Module in accordance with the
Service Information.
Perform BODY VERIFICATION TEST - VER 1.
3
Turn the ignition off.
Disconnect the A/C - Heater Control 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 each of the Blower Motor
Driver circuits (cavities 2, 3, 7, and 10) in the A/C - Heater Control Module C1
harness connector.
Does the test light illuminate brightly on each circuit?
All
Yes
→ Go To 4
No
→ Go To 6
233
HEATING & A/C