Diagnostic Test

WARNING: This page is about a different car, the 2015 RAM 3500 HD and 2015 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

RADIATOR COOLING FAN MODULE OPERATION
1. Turn the ignition on.
2. With a scan tool, actuate both the Radiator Cooling Fan Relays No. 1 and No. 2.
  Are both cooling fans operating at medium speed?
  
  Yes
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
  No
  - Go To 2
CHECK THE (N112) RADIATOR FAN RELAY CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Remove the Radiator Fan High Speed Relay.
3. Disconnect the PCM C1 harness connector.
  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 the GPEC Diagnostic Adaptor to perform the diagnosis.
4. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
5. Measure the resistance of the (N112) Radiator Fan Relay Control circuit between the High Radiator Fan Relay harness connector and the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (N112) Radiator Fan Relay Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (N112) RADIATOR FAN RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Check for continuity between ground and the (N112) Radiator Fan Relay Control circuit at the GPEC Adaptor.
  Is there continuity between ground and the (N112) Radiator Fan Relay Control circuit?
  
  Yes
  - Repair the (N112) Radiator Fan Relay Control circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .