GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference Outside Rearview Mirror Schematics

1

Did you perform the Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Power Door Systems

2

Verify the fault is present.

Does the system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

Depress the rear defogger switch once.

Does the rear defogger system operate?

--

Go to Step 4

Go to Rear Window Defogger Inoperative

4

Inspect the HTD MIR fuse in the engine wiring harness junction block to see if it is open.

Is the HTD MIR fuse open?

--

Go to Step 5

Go to Step 6

5

Test the output circuit of the RR Defog relay for a short to ground.

Refer to Circuit Testing and Wiring Repairs in wiring systems.

Did you find and repair a short to ground in the circuit?

--

Go to Step 10

Go to Step 7

6

Test for a loose connection or an open in the output circuit of the RR Defog relay. Refer to Circuit Testing and Wiring Repairs in wiring systems.

Did you find and repair a loose connection or an open in the circuit?

--

Go to Step 10

Go to Heated Mirrors Inoperative - Left Side or Heated Mirrors Inoperative - Right Side

7

1. Disconnect the RH heated mirror.

2.Install a new fuse in the circuit.

3. operate the rear defog switch.

Does the system operate?

--

Go to Step 8

Go to Step 9

8

Replace the RH heated mirror. Refer to Outside Rearview Mirror Replacement .

Is the repir complete?

--

Go to Step 10

--

9

Replace the LH heated mirror. Refer to Outside Rearview Mirror Replacement .

Is the repir complete?

--

Go to Step 10

--

10

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 3