Dodge Ram Truck 1500-2500-3500. Manual — part 1134

P2504-CHARGING SYSTEM OUTPUT HIGH (CONTINUED)

7.

GENERATOR

Disconnect the Generator field harness connector.

NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between the generator field terminals at the
generator.

Is the resistance between .5 and 15 Ohms?

Yes

>> Go To 8

No

>> Replace the generator.

Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

8.

ECM

Measure and record the voltage between battery positive circuit of the
ECM harness connector and the battery negative circuits of the ECM
harness connector.

Reconnect the ECM connectors.

Use the scan tool to measure and record battery voltage.

Compare the voltage reading from the voltmeter with that of the scan
tool.

Are the readings within 3 volts of each other?

Yes

>> Refer to the INTERMITTENT CONDITION Symptom

(Diagnostic Procedure). (Refer to 9 - ENGINE - DIAGNO-
SIS AND TESTING)

No

>> Replace and program the ECM in accordance with the

Service Information.

Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

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ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

DR/DH

P2509-POWERDOWN DATA LOST ERROR

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

9 - 1459

P2509-POWERDOWN DATA LOST ERROR (CONTINUED)

For the Engine circuit diagram (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CON-
TROL MODULE - SCHEMATIC - ELECTRICAL)

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
Continuous - key on or key off.

•

Set Condition:
Loss of voltage detected at the ECM for a calibrated amount of time.

Possible Causes

POOR CONNECTIONS AT THE BATTERIES

LOW BATTERY VOLTAGE

OPEN FUSED B+ TO ECM

OPEN GROUND CIRCUIT

BATTERY + SHORTED TO OTHER CIRCUITS

RETURN CIRCUIT SHORTED

BATTERY + SHORTED TO GROUND

INTERMITTENT CONDITION

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)

Diagnostic Test

1.

POOR CONNECTIONS AT THE BATTERIES

Visually inspect the wiring at the battery for damaged wires, or corrosion.

Are the connections tight and free of corrosion?

Yes

>> Go To 2

No

>> Repair the poor connections at the batteries.

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

2.

LOW BATTERY VOLTAGE

Measure the voltage between the positive and negative posts of the batteries.

Is the battery voltages both above 12 volts?

Yes

>> Go To 3

No

>> Recharge or replace the battery (s).

Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL). (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/ENGINE CONTROL MODULE - DIAGNOSIS AND TESTING)

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ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

DR/DH

P2509-POWERDOWN DATA LOST ERROR (CONTINUED)

3.

OPEN FUSED B+ TO ECM

Turn the ignition off.

Disconnect the ECM harness connectors.

Turn the ignition on.

Measure the resistance between the positive battery post and the
ECM supply circuits.

Is the resistance less than 10 Ohms?

Yes

>> Go To 4

No

>> Repair the open fused B+ circuit to ECM.

Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

4.

OPEN GROUND CIRCUIT

Measure the resistance between the negative battery post and the
ECM ground circuits.

Is the resistance less than 10 Ohms?

Yes

>> Go To 5

No

>> Repair the open ground circuit.

Perform POWERTRAIN VERIFICATION TEST VER - 1
(DIESEL). (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/ENGINE CONTROL MODULE - DIAG-
NOSIS AND TESTING)

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - DIESEL

9 - 1461