GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Charging System Check ?

--

Go to Step 2

Go to Charging System Check

2

Check the battery hydrometer.

Is the green dot visible in the hydrometer?

--

Go to Step 7

Go to Step 3

3

Diagnose the battery hydrometer. Refer to Battery Hydrometer Displays Dark or Yellow Dot .

Is the charging system diagnosis complete?

--

Go to Step 16

--

4

Perform the battery load test. Refer to Battery Not Operating Properly .

Did the battery pass the load test?

--

Go to Step 6

Go to Step 5

5

Replace the battery. Refer to Battery Replacement .

Is the repair complete?

--

Go to Step 16

--

6

Check the generator. Refer to Generator Not Operating Properly .

Does the generator operate properly?

--

Go to Step 7

Go to Step 15

7

  1. Disconnect the generator connector.
  2. Attach a fused jumper between the generator connector terminal B and ground.
  3. Turn the ignition switch to ON.

Is the charge indicator on?

--

Go to Step 10

Go to Step 8

8

  1. Disconnect powertrain control module (PCM) connector C1.
  2. Attach a fused jumper between PCM connector C1 terminal 75 and ground.

Is the charge indicator on?

--

Go to Step 12

Go to Step 9

9

Service the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Step 16

--

10

Check for poor terminal contact at generator connector terminal B.

Is the connector terminal contact OK?

--

Go to Step 12

Go to Step 11

11

Repair or replace the generator connector.

Is the repair complete?

--

Go to Step 16

--

12

Check CKT 225 (RED) for an open.

Is the circuit OK?

--

Go to Step 14

Go to Step 13

13

Repair CKT 225 (RED).

Is the repair complete?

--

Go to Step 16

--

14

  1. Check the PCM connector C1 for poor terminal contact.
  2. If OK, replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.6L.

Is the repair complete?

--

Go to Step 16

--

15

Replace the generator. Refer to Generator Replacement .

Is the repair complete?

--

Go to Step 16

--

16

Repeat the Charging System Check. Refer to Charging System Check .

Is the system check complete?

--

System OK

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