Diagnostic Test

1) FUEL PUMP OPERATION
Ignition on, engine not running.

With a scan tool in the Powertrain Actuators, actuate the Fuel Pump.

Is the Fuel Pump operating?

Yes
1. Refer to the INTERMITTENT CONDITION diagnostic procedure.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 2).
2) FUEL PUMP CONTROL OPERATION FROM THE PCM

Fig 1: MEASURING VOLTAGE AT THE FUEL PUMP CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the TIPM C2 harness connector.

Turn the ignition on.

Using the scan tool in the Powertrain Actuators, actuate the Fuel Pump.

With a 12-volt test light connected to ground, probe the Fuel Pump Control circuit in the TIPM C2 harness connector.

Does the test light illuminate brightly and flash on and off?

Yes
1. If OK, replace the TIPM in accordance with the Service Information.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 3).
3) (K31) FUEL PUMP CONTROL CIRCUIT SHORTED TO BATTERY VOLTAGE

Fig 2: MEASURING VOLTAGE AT THE FUEL PUMP CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Stop the Fuel Pump actuation.

Turn the ignition off.

Disconnect the PCM C3 harness connector.

Turn the ignition on.

Measure the voltage of the (K31) Fuel Pump Control circuit at the TIPM C2 harness connector.

Does the voltmeter indicate voltage present?

Yes
1. Repair the short to voltage in the (K31) Fuel Pump Relay Control circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 4).
4) (K31) FUEL PUMP CONTROL CIRCUIT OPEN

Fig 3: MEASURING RESISTANCE OF THE FUEL PUMP CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

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 to perform diagnosis.

Measure the resistance of the (K31) Fuel Pump Control circuit from the TIPM harness connector to the appropriate terminal of special tool #8815.

Is the resistance below 5.0 ohms?

Yes
1. Go To 5).
No
1. Repair the open in the (K31) Fuel Pump Control circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
5) (K31) FUEL PUMP CONTROL CIRCUIT SHORTED TO GROUND

Fig 4: MEASURING RESISTANCE BETWEEN GROUND AND FUEL PUMP CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the (K31) Fuel Pump Control circuit in the TIPM C2 harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (K31) Fuel Pump Control circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 6).
6) PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes
1. Repair as necessary.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE-POWERTRAIN CONTROL and STANDARD PROCEDURE - PCM/ECM/SKREEM PROGRAMMING .
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .