Heater Blower Motor Does Not Run At Any Speed

WARNING: This page is about a different car, the 1995 Ford Probe. However, it is still accessible from the selected car via links, so may be relevant.

Check Fuses
Turn ignition off. Locate 15-amp ENGINE fuse in interior fuse junction panel located behind left side kick panel. Locate 40-amp HEATER fuse in main fuse junction panel located behind battery. If fuses are okay, go to step 4). If fuse(s) are not okay, go to next step.
Check System
Turn ignition off and replace blown fuse(s). Turn ignition on. If fuse(s) blow again, go to next step. If fuse(s) do not fail again, go to step 4).
Check For Short(s) To Ground
Turn ignition off. Disconnect interior fuse junction panel 10-pin connector. Remove 40-amp HEATER fuse from main fuse junction panel. Disconnect blower motor No. 1 relay connector, located at right front side of radiator.

Measure resistance between ground and fuse junction panel 10-pin connector terminal No. 2 (Black/White wire). Measure resistance between ground and 40-amp HEATER fuse holder left terminal (Blue wire). If resistance is greater than 5 ohms, repair short to ground. If resistance is less than 5 ohms, restore connections, install fuses, and go to next step.
Check Heater Blower Motor
Turn ignition off and disconnect heater blower motor 2-pin connector. Connect battery voltage to heater blower motor 2-pin connector White wire and ground to connector Blue/Orange wire. If heater blower motor operates, go to next step. If heater blower motor does not operate, replace blower motor.

Check Heater Blower Motor Switch

Turn ignition off and disconnect heater blower motor switch connector. Measure resistance between heater blower motor switch terminals with switch in each specified position. See HEATER BLOWER MOTOR SWITCH TESTING table. If resistance is as specified, go to next step. If resistance is not as specified, replace heater blower motor switch.

HEATER BLOWER MOTOR SWITCH TESTING

Switch Position

Test Between Terminals

Ohms

All

⁽¹⁾10,000

2nd

BLU/YEL & BLU

⁽²⁾5

2nd

All Others

⁽¹⁾10,000

3rd

BLU/YEL & BLU

⁽²⁾5

3rd

BLU/YEL & YEL/BLK

⁽²⁾5

3rd

BLU & YEL/BLK

⁽²⁾5

3rd

All Others

⁽¹⁾10,000

BLU/YEL & YEL/BLK

⁽²⁾5

BLU/YEL & BLU/WHT

⁽²⁾5

YEL/BLK & BLU/WHT

⁽²⁾5

All Others

⁽¹⁾10,000

⁽¹⁾	More than.

⁽²⁾	Less than.

Check Mode Selector Switch
Disconnect mode selector switch connector, located behind control panel. Measure resistance between mode selector switch Blue/Yellow wire and Black wire terminals. With switch in OFF position, resistance should be more than 10,000 ohms. With switch in any other position, resistance should be less than 5 ohms. If resistance is as specified, go to next step. If resistance is not as specified, replace mode selector switch.
Check Mode Selector Switch Ground
Disconnect mode selector switch. Measure resistance between mode selector switch connector Black wire and ground. If resistance is less than 5 ohms, reconnect mode selector switch connector and go to next step. If resistance is not less than 5 ohms, repair Black wire between switch connector and ground.
Check Blower Motor No. 1 Relay
Turn ignition off. Locate blower motor No. 1 relay at right side of radiator and disconnect connector. Connect battery voltage to blower motor No. 1 relay Black/White wire terminal. Connect ground lead to blower motor No. 1 relay Black/Red wire terminal. Measure resistance between blower motor No. 1 relay Blue wire and White wire terminals. If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, replace blower motor No. 1 relay.
Check Power To Blower Motor No. 1 Relay
Turn ignition off. Locate blower motor No. 1 relay at right side of radiator and disconnect connector. Turn ignition on. Measure voltage between blower motor No. 1 relay connector Blue wire terminal and ground, and between Black/White wire terminal and ground. If voltage is more than 10 volts, turn ignition off and go to next step. If voltage is not more than 10 volts, repair wire circuit(s).
Check Blower Motor No. 1 Relay Ground
Turn ignition off. Locate blower motor No. 1 relay at right side of radiator and disconnect connector. Measure resistance between ground and blower motor No. 1 relay connector Black/Red wire terminal. If resistance is less than 5 ohms, go to next step. If resistance is not less than 5 ohms, repair Black/Red wire circuit.

Check Heater Blower Motor Resistor

Turn ignition switch off and disconnect blower motor resistor connector. Using a DVOM, measure resistance between terminals indicated in BLOWER MOTOR RESISTOR TESTING table. If resistance is as specified, go to next step. Replace heater blower motor resistor if resistance readings are not as specified.

BLOWER MOTOR RESISTOR TESTING

Terminal No. (Wire Color)	Ohms
1 (GRN/RED) & 4 (BLU/WHT)	2.76
1 (GRN/RED) & 2 (BLU)	1.69
2 (BLU) & 3 (RED/BLK)	0.69
3 (RED/BLK) & 4 (BLU/WHT)	0.38

Check Wire Between Blower Motor No. 1 Relay & Heater Blower Motor
Turn ignition off. Locate blower motor No. 1 relay at right side of radiator and disconnect connector. Disconnect heater blower motor connector. Measure resistance between White wire terminal at blower motor No. 1 relay connector and heater blower motor. If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair White wire circuit.
Check Wire Between Heater Blower Motor & Heater Blower Motor Resistor
Disconnect heater blower motor and heater blower motor resistor connectors. Measure Blue/Orange wire resistance between heater blower motor connector and heater blower motor resistor connector. If resistance is less than 5 ohms, repair Blue/Yellow wire circuit between heater blower motor switch and mode selector switch. If resistance is greater than 5 ohms, repair Blue/Orange wire.