1. Disconnect the blower motor resistor connector.
2. Turn the ignition switch to the ON position.
3. Place the heater-A/C control in the VENT position.
4. Place the blower switch to the inoperative position.
5. Using a test light, backprobe between ground and the blower motor resistor connector terminal listed below:

•	LO: Terminal B.

•	M1: Terminal A.

•	M2: Terminal D.

•	M3: Terminal C.

Does the test light illuminate?

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Go to Step 2

Go to Step 3

Replace the blower motor resistor. Refer to Blower Motor Resistor Replacement

Has the repair been made and the system rechecked?

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Go to Step 6

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1. Turn the ignition switch to the OFF position.
2. Keep the blower motor resistor connector disconnected.
3. Disconnect the heater-A/C control connector C1.
4. Check for a poor connection or an open in the inoperative circuit listed below: Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

•	LO: Terminal B.

•	M1: Terminal A.

•	M2: Terminal D.

•	M3: Terminal C.

Is there a poor connector, an open, or a short to ground in the inoperative circuit tested?

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Go to Step 4

Go to Step 5

Locate and repair the fault in the circuit. Refer to Wiring Repairs in Wirirng Systems.

Is the repair complete?

--

Go to Step 6

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Replace the heater-A/C control. Refer to Control Assembly Replacement .

Is the repair complete?

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Go to Step 6

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Verify that the system operates properly.

Does the system operate properly?

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System OK

Go to Symptoms