NGC

P2504-CHARGING SYSTEM OUTPUT HIGH





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on. Engine RPM greater than 1000 RPM. With no other charging system codes set.

- Set Condition:
The alternator B+ voltage sense circuit voltage reading exceeds the direct Battery B+ sense circuit. The Generator output terminal is not connected to the Battery B+ post. One trip fault.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview

Diagnostic Test

1. ACTIVE DTC
NOTE: Inspect the vehicle for aftermarket accessories that may exceed the Generator System output.

NOTE: The battery must be fully charged.

NOTE: The Generator belt tension and condition must be checked before continuing.

Ignition on, engine not running.
With a scan tool, select View DTCs and record the related Freeze Frame data.
With the scan tool erase DTCs.
Start the engine.
Allow the idle to stabilize.
With the scan tool, select View DTCs.
Is the DTC Active at this time?

Yes

- Go to 2

No

- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.Checking For An Intermittent DTC

2. (A801) BATTERY POSITIVE CIRCUIT VISUAL INSPECTION
Turn the ignition off.
Inspect the (A801) Battery Positive circuit at Generator Output post for corrosion and looseness.
Inspect the Battery + and - cables for corrosion and looseness.
Inspect the (A0) Battery Positive circuit at the C8 TIPM harness connector for corrosion and looseness.
Were any problems found?

Yes

- Repair and replace as necessary.
- Perform PCM Verification Test. Powertrain Verification Test

No

- Go to 3

3. EXCESSIVE RESISTANCE IN THE (A209) BATTERY FEED CIRCUIT
CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 and #8815-1 to perform diagnosis.

Disconnect the C1 PCM harness connector.
Perform a voltage drop test on the (A209) Battery Feed circuit from the appropriate terminals of special tool #8815-1 to the C2 TIPM harness connector.
Using a voltmeter probe the appropriate terminal of special tool #8815-1 with the Negative lead of the voltmeter and back probe the (A209) Battery Feed circuit at the C2 TIPM harness connector with the Positive lead of the voltmeter.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Start the engine
Monitor the voltmeter.
Is the voltage above 0.4 of a volt?

Yes

- Repair the excessive resistance in the (A209) Battery Positive circuit between the PCM and TIPM.
- Perform PCM Verification Test. Powertrain Verification Test

No

- Go to 4

4. POWERTRAIN CONTROL MODULE (PCM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Generator and the Powertrain Control Module (PCM).
Look for any chafed, pierced, pinched, or partially broken wires.
Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Generator and Powertrain Control Module connectors.
Search for any Technical Service Bulletins that may apply.
Were there any problems found?

Yes

- Repair as necessary.
- Perform PCM Verification Test. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module.
- Perform PCM Verification Test. Powertrain Verification Test