Cooling Fan Relay

Replace the cooling fan relay to restore proper electric cooling fan operation on a 2014 Ram 2500 with 6.7L Cummins diesel engine.

Warnings

Tools required

Parts

• Cooling fan relay × 1 — Use OEM specification - typically Mopar 04692373 or equivalent

Preparation

1. Ensure engine is off and key is removed from ignition
2. Allow engine compartment to cool if vehicle was recently operated
3. Locate the Power Distribution Center on the driver's side of engine compartment, near the battery
4. Identify the cooling fan relay using the PDC cover diagram (typically labeled as fan relay or high-speed fan relay)

Procedure

1. 1

   Disconnect negative battery cable
   Using a 10mm socket, loosen and remove the negative battery cable from the battery terminal. Secure the cable away from the battery to prevent accidental reconnection during relay replacement.
2. 2

   Access Power Distribution Center
   Locate the PDC on the driver's side of the engine compartment. Release the locking tabs on both sides of the PDC cover and carefully lift the cover upward to expose the relays and fuses. The PDC cover contains a diagram showing relay locations.
3. 3

   Identify cooling fan relay
   Reference the diagram on the underside of the PDC cover or in the owner's manual to identify the cooling fan relay position. The 2014 Ram 2500 typically has multiple fan relays (low-speed and high-speed). Identify which relay corresponds to your cooling fan issue. The relays are typically black rectangular components with 4 or 5 pins.
4. 4

   Test relay operation (optional)
   Before removal, if you have a multimeter, you can test the relay for continuity and proper operation. Check for 12V power at the appropriate terminals with key on. This step helps confirm the relay is the faulty component rather than wiring or the fan motor itself.
5. 5

   Remove faulty cooling fan relay
   Firmly grasp the relay body and pull straight upward with steady force to remove it from the PDC socket. The relay fits tightly into the socket and may require significant force. If available, use a relay puller tool to avoid damage to surrounding components. Avoid rocking the relay side to side excessively as this can damage the socket terminals.
6. 6

   Inspect relay socket
   Examine the relay socket in the PDC for any signs of corrosion, melting, or damage to the terminals. Check for burned or discolored plastic which may indicate overheating. If corrosion is present, clean terminals with electrical contact cleaner. If socket is damaged, the entire PDC may require replacement.
7. 7

   Install new cooling fan relay
   Align the new relay with the socket, ensuring the relay pins match the socket configuration. Apply a small amount of dielectric grease to the relay pins if desired to prevent corrosion. Press the relay firmly into the socket until it seats completely and is flush with surrounding relays. The relay should click into place and feel secure.
8. 8

   Reinstall PDC cover
   Position the PDC cover over the fuse and relay box, ensuring all wiring is clear of the cover edges. Press down on both sides until the locking tabs engage with an audible click. Verify the cover is fully seated and secure.
9. 9

   Reconnect battery
   Reconnect the negative battery cable to the battery terminal and tighten securely with a 10mm socket. Ensure the connection is tight to prevent starting or charging issues.

Reassembly

1. Verify PDC cover is properly secured and all locking tabs are engaged
2. Ensure no tools or parts are left in the engine compartment
3. Close hood and prepare for system verification

Verification

• Start the engine and allow it to reach operating temperature while monitoring coolant temperature gauge
• Listen and watch for cooling fan activation when engine reaches normal operating temperature (approximately 200-210°F)
• With engine at operating temperature, turn on air conditioning to maximum - this should trigger cooling fan operation immediately
• If fan does not operate, verify relay installation is correct and check for other potential issues such as fan motor failure, temperature sensors, or wiring problems
• Scan for diagnostic trouble codes using an OBD-II scanner to confirm no cooling system faults are present

Related trouble codes on this vehicle

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