GM Service Manual Online
For 1990-2009 cars only

Diagnostic Aids

If the power windows operate properly under RAP conditions and the Radio or VIU do not operate properly, the condition may exist in the class 2 circuit of the Radio, VIU or IPC, or one of the individual modules. Refer to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications.

Step

Action

Yes

No

Schematic Reference: Retained Accessory Power (RAP) Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems

1

Did you perform the RAP Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Retained Accessory Power

2

  1. Close the driver and passenger doors.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn OFF the ignition.

Do the power windows and power quarter vents operate for approximately 10 minutes?

Go to Step 3

Go to Step 6

3

  1. Close the driver and passenger doors.
  2. Turn ON the ignition, with the engine OFF.
  3. Turn OFF the ignition.

Do the radio and VIU operate for approximately 10 minutes?

System OK

Go to Step 4

4

Test the RAP control circuit at the IPC for an open or intermittent condition. Refer to Circuit Testing , Testing for Intermittent Conditions and Poor Connections and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 5

5

Important: Perform the setup procedure for the IPC. Refer to Instrument Cluster Programming/Synchronization in Instrument Panel, Gages and Console.

Replace the IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gages and Console.

Did you complete the replacement?

Go to Step 14

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6

  1. Turn OFF the ignition.
  2. Disconnect the RAP relay.
  3. Probe the battery positive voltage circuits of the RAP relay with a test lamp that is connected to a good ground.

Does the test lamp illuminate on both circuits?

Go to Step 7

Go to Step 11

7

  1. Connect a test lamp between the control circuit of the RAP relay and the battery positive voltage circuit of the RAP relay.
  2. Close the driver and passenger doors.
  3. Turn ON the ignition, with the engine OFF.
  4. Turn OFF the ignition.

Does the test lamp illuminate?

Go to Step 9

Go to Step 8

8

Test the control circuit of the RAP relay for a short to voltage or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 10

9

Inspect for poor connections at the RAP relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 12

10

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 14

Go to Step 13

11

  1. Repair the battery positive voltage circuit of the RAP relay. Refer to Wiring Repairs in Wiring Systems.
  2. Reconnect the RAP relay.

Did you complete the repair?

Go to Step 14

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12

Replace the RAP relay.

Did you complete the replacement?

Go to Step 14

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13

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 14

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14

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 6