GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Schematic Reference: Starting and Charging Schematics

Connector End View Reference: Engine Electrical Connector End Views , Engine Control Module Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Start the engine.
  2. Turn OFF all accessories.

Does the battery charge indicator remain illuminated?

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Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Install a scan tool.
  2. Start the engine.
  3. Turn OFF all accessories.
  4. Increase engine speed to 1,500 RPM.
  5. With a scan tool, observe the Battery Voltage Signal parameter in the body control module (BCM) data list, engine control module (ECM) data list, and the instrument panel cluster (IPC) data list.
  6. Compare the voltages.

Are all of the voltages within the specified range?

0.9-1.1 V

Go to Step 4

Go to Step 5

4

Are the voltages displayed within the specified range?

11-16 V

Go to Step 5

Go to Charging System Test

5

Test the battery positive voltage and ground circuits of the affected module for a high resistance or open. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

--

Go to Step 8

Go to Step 6

6

Inspect for poor connections at the harness connector of the affected module. Refer to Connector Repairs .

Did you find and correct the condition?

--

Go to Step 8

Go to Step 7

7

Replace the affected module. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 8

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8

Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 2