Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Test Description
2004 Pontiac GTO StandardSECTION Test Description
The step below refers to the test step on the diagnostic table.
- 10: If the test has shown the generator to be OK, however the condition remains, test the PCM or its control circuit(s) to the generator.
Charging System Test
| Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
| 1 | Did you perform the Diagnostic System Check for Engine Electrical? | - | Go to Step 2 | Go to Diagnostic System Check - Engine Electrical |
| 2 | Start the engine, observe the charge indicator on the instrument cluster (IPC) or message in the driver information center (DIC). Does the charge indicator illuminate or the DIC display a charging system message? |
- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
| 3 |
IMPORTANT:
The green POWER lamp of the tester should remain illuminated while the tester is being used.
|
- | Go to Step 6 | Go to Step 4 |
| 4 | Measure the voltage from the output terminal of the generator to the generator metal housing. Does the voltage measure equal to the specified value? |
B + | Go to Step 14 | Go to Step 5 |
| 5 | Measure the voltage from the output terminal of the generator to the battery negative terminal. Does the voltage measure equal to the specified value? |
B + | Go to Step 12 | Go to Step 11 |
| 6 |
CAUTION:
Make sure that the load is completely turned off before connecting or disconnecting a carbon pile load tester to the battery. Otherwise, sparking could ignite battery gasses which are extremely flammable and may explode violently.
IMPORTANT:
Be sure all of generator output circuit wires pass through the inductive probe.
|
- | Go to Step 7 | Go to Step 13 |
| 7 |
|
- | Go to Step 15 | Go to Step 8 |
| 8 |
|
- | Go to Step 15 | Go to Step 9 |
| 9 |
|
0.5 V | Go to Step 11 | Go to Step 10 |
| 10 |
|
0.5 V | Go to Step 12 | Go to Step 16 |
| 11 | Repair the high resistance or an open in the output circuit of the generator. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 16 | - |
| 12 | Repair the high resistance or open in the ground circuit of the generator. Refer to Circuit Testing
and Wiring Repairs
in Wiring Systems. Did you complete the repair? |
- | Go to Step 16 | - |
| 13 |
|
- | Go to Step 15 | Go to Step 14 |
| 14 | There is a problem with the J 41450-B
. See Special Tools and Equipment . Refer to the manufacturers instructions, how to test the J 41450-B
for proper operation. See Special Tools and Equipment . Has the J 41450-B tester been replaced? See Special Tools and Equipment . |
- | Go to Step 3 | - |
| 15 | Replace the generator. Refer to Generator Replacement . Did you complete the replacement? |
- | Go to Step 16 | - |
| 16 | Operate the vehicle in order to verify the repair. Did you correct the condition? |
- | System OK | Go to Step 2 |
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.