Main Relay

Replace the main power distribution relay in the Power Distribution Center (PDC) located in the engine compartment, which controls primary electrical system functions.

Warnings

Tools required

Parts

• Main relay (TIPM/PDC relay) × 1 — Use OEM specification - Mopar 68105077AB or equivalent

Preparation

1. Park vehicle on level surface and ensure ignition is off
2. Allow engine to cool if recently operated
3. Locate the Power Distribution Center (PDC) on the driver's side of the engine compartment near the battery
4. Note radio presets and any custom settings that will be lost

Procedure

1. 1

   Disconnect battery negative terminal
   Using a 10mm socket, loosen the negative battery terminal bolt. Remove the negative cable from the battery post and secure it away from the terminal to prevent accidental reconnection. Wait 2 minutes for system capacitors to discharge.
   Torque spec

   Battery Terminal Bolts6 Nm (4 lb-ft)
2. 2

   Access Power Distribution Center
   Locate the PDC cover on the driver's side fender well in the engine compartment. Release the retaining tabs on both sides of the cover by pressing inward and lifting up. Set the cover aside in a clean location - the relay diagram on the underside will be needed for reference.
3. 3

   Identify main relay position
   Refer to the relay diagram on the PDC cover to identify the exact location of the main relay. On 2014 Ram 2500 models, this is typically a large relay in the center section of the PDC. Verify relay identification by comparing physical relay to diagram specifications.
4. 4

   Remove main relay
   Grasp the main relay firmly and pull straight up with steady pressure to disengage it from the socket. If resistance is encountered, use a relay puller tool or gently rock the relay side-to-side while pulling upward. Avoid prying or using excessive force which could damage the socket terminals.
5. 5

   Inspect relay socket and terminals
   Examine the relay socket for corrosion, bent pins, or debris. Check that all socket terminals are clean and properly aligned. If corrosion is present, clean terminals with electrical contact cleaner and allow to dry. Inspect the old relay terminals for signs of overheating, melting, or damage.
6. 6

   Install new main relay
   Apply a small amount of dielectric grease to the relay terminals if desired. Align the new relay with the socket, ensuring proper orientation by matching the relay tab or notch with the socket guide. Press the relay firmly into the socket until it seats completely with an audible click. Verify the relay is fully seated and flush with surrounding relays.
7. 7

   Reinstall PDC cover
   Position the PDC cover over the distribution center, aligning the cover tabs with the PDC housing. Press down firmly on both sides until the retaining tabs click into place. Ensure the cover is fully seated and secure.
8. 8

   Reconnect battery negative terminal
   Clean the battery post and cable terminal with a wire brush if corrosion is present. Place the negative cable onto the battery post and tighten the terminal bolt to specification using a torque wrench. Ensure the connection is secure but do not overtighten.
   ⚠Do not overtighten battery terminal - torque specification is critical to prevent terminal damage
   Torque spec

   Battery Terminal Bolts6 Nm (4 lb-ft)

Reassembly

1. Verify PDC cover is properly secured with all tabs engaged
2. Confirm battery terminal connection is clean and tight to specification
3. Reset clock and radio presets as needed

Verification

• Turn ignition to ON position (do not start) and verify dash warning lights illuminate normally then extinguish
• Start the engine and confirm normal operation with no warning lights
• Test primary electrical systems including lights, power windows, and horn to verify relay function
• Check for any diagnostic trouble codes using a scan tool
• Verify no electrical faults are present and all systems operate normally

Related trouble codes on this vehicle

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