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TROUBLESHOOTING GUIDE — Blower motor does not operate

U-7prose procedure

Symptom: Blower motor does not operate.

Normal operation of blower motor

Blower motor speed is controlled by the blower switch and a resistor assembly in the blower unit.
When the blower switch is in the OFF position, the motor ground circuit is open and the blower motor does not operate. When the switch is in the first (Low) position, current flow from the blower motor is restricted by the three resistors in the resistor assembly, and the blower motor turns at low speed.
Changing the blower switch to the second (Mid), third (High), or fourth (Super-high) position causes the circuit resistance to decrease, and the blower motor speed becomes correspondingly faster.

Step 1

  1. 1
    Check the circuit breaker.
    Illustration of the fuse box with the HEATER 30A fuse highlighted at top. A 'RED BUTTON' (circuit breaker reset) is labeled at the bottom of the box.
    05U0UX-082
  2. 2
    If the reset button is not out, go to Step 2.
  3. 3
    If the reset button is out, check for a short circuit in the harness. Repair as necessary; then depress the reset button to reset the circuit breaker.

Step 1 — Heater circuit breaker

HEATER
Amperage30A
LocationFuse box

Step 2

  1. 1
    Turn the ignition switch ON.
  2. 2
    Turn the blower switch to the fourth position.
  3. 3
    Measure the voltage at terminal-wire (L) of the blower motor connector.
    Illustration of the blower motor mounted under the dash with the connector pulled out and terminal (L) — Blue wire — highlighted on the connector for voltage measurement.
    05U0UX-007

Step 2 — Blower motor connector voltage

(L)
Voltage12V
ActionGo to Step 3
(L)
Voltage0V
ActionRepair wire harness (Circuit breaker—Blower motor)
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See also

Step 2 · Step 3

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