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For 1990-2009 cars only

Blower Motor Inoperative in One Speed Only Front, High Speed Operates Normally

Step

Action

Value(s)

Yes

No

1

Did you review the Blower Controls Circuit Description and perform the necessary inspections?

--

Go to Step 2

Go to Symptoms

2

Verify that the front blower motor operates in one speed only (high speed operates normally).

Does the front blower motor operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Disconnect the blower motor resistor connector.
  2. Place the ignition switch in the RUN position.
  3. Place the heater-A/C control in the inoperative position.
  4. Connect a test lamp from the blower motor resistor connector inoperative terminal (1=B, 2=A, 3=D, 4=C) to ground on the harness connector. Refer to Circuit Testing in Wiring Systems.

Is the test lamp on?

--

Go to Step 4

Go to Step 5

4

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

Is the repair complete?

--

Go to Step 8

--

5

Probe with a test lamp between the heater-A/C control connector C1 of the inoperative terminal (1=H, 2=G, 3=F, 4=E) and ground. Refer to Circuit Testing in Wiring Systems.

Is the test light on?

--

Go to Step 6

Go to Step 7

6

Repair the poor connection or an open in the inoperative circuit (1=60, 2=63, 3=72, 4=73). Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 8

--

7

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

Is the repair complete?

--

Go to Step 8

--

8

  1. Turn the ignition switch to the OFF position.
  2. Reconnect all connectors/components disconnected.
  3. Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3

Blower Motor Inoperative in One Speed Only Rear, High Speed Operates Normally

Step

Action

Value(s)

Yes

No

1

Did you review the Blower Controls Circuit Description and perform the necessary inspections?

--

Go to Step 2

Go to Symptoms

2

Verify that the rear blower motor operates in one speed only (high speed operates normally).

Does the rear blower motor operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Is one speed inoperative from the auxiliary heater-A/C control (auxiliary blower switch) only?

--

Go to Step 4

Go to Step 5

4

  1. Place the ignition switch in the RUN position.
  2. Turn the rear window wiper/washer and multi-function switch to the rear position.
  3. Place the auxiliary heater-A/C control (auxiliary blower switch) in the inoperative position.
  4. Connect a test lamp from the auxiliary heater-A/C control connector C2 inoperative terminal (1=D, 2=E, 3=F) to B+. Refer to Circuit Testing in Wiring Systems.

Is the test lamp on?

--

Go to Step 6

Go to Step 7

5

Is one speed inoperative from the rear window wiper/washer and multifunction switch (auxiliary blower switch) only?

--

Go to Step 8

Go to Step 9

6

Repair the poor connection or open in the inoperative circuit (1=1176, 2=1072, 3=1052). Refer to Wiring Repairs or Connector Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 12

--

7

Replace the auxiliary heater-A/C control. Refer to Auxiliary HVAC Module Replacement .

Is the repair complete?

--

Go to Step 12

--

8

Probe with a test lamp between the rear window wiper/washer and multi-function switch connector C2 of the inoperative terminal (1=A, 2=C, 3=B) and B+. Refer to Circuit Testing in Wiring Systems.

Is the test lamp on?

--

Go to Step 6

Go to Step 10

9

  1. One speed is inoperative from both switches.
  2. Disconnect the auxiliary blower motor resistor connector.
  3. Place the auxiliary blower switch in the inoperative position.
  4. Connect a test lamp from the auxiliary blower motor resistor connector inoperative terminal (1=C, 2=D, 3=B) to B+. Refer to Circuit Testing in Wiring Systems.

Is the test lamp on?

--

Go to Step 11

Go to Step 6

10

Replace the rear window wiper/washer and multi-function switch. Refer to Auxiliary Air Conditioning (A/C) Control Assembly Replacement - Front .

Is the repair complete?

--

Go to Step 12

--

11

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

Is the repair complete?

--

Go to Step 12

--

12

  1. Turn the ignition switch to the OFF position.
  2. Reconnect all connectors/components disconnected.
  3. Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3