Diagnostic Test

WARNING: This page is about a different car, the 2007 Dodge Sprinter. However, it is still accessible from the selected car via links, so may be relevant.

1) TEST FOR INTERMITTENT CONDITION
NOTE: This diagnostic test may apply to either Auxiliary Heater Module on the vehicle.

Turn the ignition on.

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.

With the scan tool, select ECU view.

NOTE: A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.

Does the scan tool display a red X next to the module?

Yes
1. Go To step 2).
No
1. The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
2) GROUND CIRCUIT OPEN

Fig 1: Auxiliary Heater Module Harness Connectors - Pins 2
Courtesy of CHRYSLER LLC

Turn the ignition off.

Using a 12-volt test light connected to 12-volts, check the ground circuit.

Does the test light illuminate brightly?

Yes
1. Go To step 3).
No
1. Repair the ground circuit for an open.
2. Perform BODY VERIFICATION TEST - VER 1 .
3) FUSED B(+) CIRCUIT OPEN OR SHORTED

Fig 2: Auxiliary Heater Module Harness Connectors - Pins 1
Courtesy of CHRYSLER LLC

Using a 12-volt test light connected to ground, check the Fused B(+) circuit.

Does the test light illuminate brightly?

Yes
1. Go To step 4).
No
1. Repair the Fused B(+) circuit for an open or short.
2. Perform BODY VERIFICATION TEST - VER 1 .
4) CAN B BUS CIRCUITS OPEN

Fig 3: Auxiliary Heater Module Harness Connectors - Pins 5 And 6
Courtesy of CHRYSLER LLC

NOTE: One open circuit will not cause this condition.

Turn the ignition on.

Measure the voltage between the CAN B Bus (-) circuit and ground.

Measure the voltage between the CAN B Bus (+) circuit and ground.

Is there any voltage present on either circuit?

Yes
1. Replace the Auxiliary Heater Module in accordance with the service information.
2. Perform BODY VERIFICATION TEST - VER 1 .
No
1. Inspect the connector for damage. Repair the CAN B Bus circuits for an open.
2. Perform BODY VERIFICATION TEST - VER 1 .