Diagnostic Test

1) RADIATOR COOLING FAN MODULE OPERATION
Ignition on, engine not running.

With a scan tool, select Radiator Cooling Fan Relay #2 Control State to actuate the Cooling Fan (High Speed).

Is the Cooling Fan 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) (A16) FUSED B+ CIRCUIT

Fig 1: Checking Fused B+ Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition off.

Disconnect the Radiator Cooling Fan Module harness connector.

Using a 12-volt test light connected to ground, probe the (A16) Fused B+ circuit in the Radiator Cooling Fan Module harness connector.

Does the test light illuminate brightly?

Yes
1. Go To 3).
No
1. Repair the (A16) Fused B+ circuit. Inspect the related fuse and repair as necessary.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
3) (Z903) GROUND CIRCUIT

Fig 2: Checking Ground Circuit
Courtesy of DAIMLERCHRYSLER CORP.

Using a 12-volt test light connected to battery voltage, probe the (Z903) Ground circuit in the Radiator Cooling Fan Module harness connector.

Does the test light illuminate brightly?

Yes
1. Go To 4).
No
1. Repair the (Z903) Ground circuits.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
4) HIGH SPEED RAD FAN CONTROL CONTROL CIRCUIT

Fig 3: CHECKING HIGH SPEED RAD FAN CONTROL CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Turn the ignition on, engine not running.

With a scan tool, select Radiator Cooling Fan Relay #2 Control State, Toggle, to actuate the Cooling Fan (High Speed).

Using a 12-volt test light connected to battery voltage, probe the (N112) High Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.

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

Yes
1. Replace the Radiator Cooling Fan Module.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 5).
5) (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT SHORTED TO BATTERY VOLTAGE

Fig 4: CHECKING HIGH SPEED RAD FAN CONTROL CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Disconnect the TIPM C11 harness connector.

Using a voltmeter, measure the voltage of the (N112) High Speed Rad Fan Control circuit in the Radiator Cooling Fan Module harness connector.

Is there voltage present?

Yes
1. Repair the short to voltage in the (N112) High Speed Rad Fan Control circuit
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Go To 6).
6) (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT OPEN

Fig 5: MEASURING RESISTANCE OF THE HIGH SPEED FAN CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance of the (N112) High Speed Fan Control circuit from the Radiator Cooling Fan Module harness connector to the TIPM C11 harness connector.

Is the resistance below 5.0 ohms?

Yes
1. Go To 7).
No
1. Repair the open in the (N112) High Speed Fan Control circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
7) (N112) HIGH SPEED RAD FAN CONTROL CIRCUIT SHORTED TO GROUND

Fig 6: MEASURING RESISTANCE BETWEEN GROUND AND THE HIGH SPEED FAN CONTROL CIRCUIT
Courtesy of DAIMLERCHRYSLER CORP.

Measure the resistance between ground and the (N112) High Speed Fan Control circuit in the TIPM C11 harness connector.

Is the resistance below 100 ohms?

Yes
1. Repair the short to ground in the (N112) High Speed Fan Control circuit.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .
No
1. Replace the Totally Integrated Power Module in accordance with the Service Information.
2. Perform the POWERTRAIN VERIFICATION TEST. (Refer to STANDARD PROCEDURE - POWERTRAIN VERIFICATION TEST) .