Blower Motor Control Module

Replace the blower motor control module (power module/resistor) that regulates HVAC blower motor speed in the 2005 Dodge Viper.

Warnings

Tools required

Parts

• Blower motor control module (power module) × 1 — Mopar 4885482AC or equivalent

Preparation

1. Park vehicle on level surface and set parking brake.
2. Turn ignition to OFF and remove key.
3. Allow HVAC system to cool if recently operated (15-20 minutes).
4. Disconnect negative battery terminal to prevent electrical shorts during connector handling.

Procedure

1. 1

   Access passenger footwell area
   Position yourself in the passenger footwell. The blower motor control module is generally mounted on the HVAC housing near the blower motor; verify exact location for the 2005 Viper (ZB) against the factory service manual before proceeding. You may need to move the passenger seat fully rearward for better access. Use a flashlight to locate the module—it will be a finned heat sink-style component mounted to the HVAC case with an electrical connector.
2. 2

   Locate blower motor control module
   Identify the blower motor control module mounted to the lower passenger side of the HVAC housing. It is a rectangular component with cooling fins and a single electrical connector. The module is positioned to use the HVAC housing as a heat sink.
3. 3

   Disconnect electrical connector
   Press the locking tab on the electrical connector and pull firmly to disconnect it from the blower motor control module. The connector may be stiff due to heat cycling. Do not pull on the wires—grip the connector body itself.
4. 4

   Remove module mounting fasteners
   Remove the mounting screws securing the blower motor control module to the HVAC housing (verify exact count and driver size against the 2005 Viper service manual). These fasteners thread directly into the plastic housing. Keep track of the screws as they are small and easily lost.
5. 5

   Remove control module
   Carefully pull the blower motor control module away from the HVAC housing. The module may have thermal grease or a rubber gasket between it and the housing for heat transfer. Note the orientation and position of any thermal interface material for reinstallation.
6. 6

   Clean mounting surface
   Clean the mounting surface on the HVAC housing where the module mounts. Remove any old thermal grease or debris using a clean cloth. The mounting surface should be clean and dry to ensure proper seating of the new module.
7. 7

   Install new control module
   Position the new blower motor control module onto the HVAC housing, aligning the mounting holes. Ensure any thermal interface material (if supplied with the new module) is properly positioned between the module and housing. The cooling fins should face outward for air circulation.
8. 8

   Install mounting fasteners
   Install the 2 mounting screws and tighten to secure the module to the HVAC housing. Tighten screws evenly in a cross pattern to ensure proper contact with the housing surface. Do not overtighten as the housing is plastic and can strip. Note: Tighten screws snugly by hand; do not overtighten into the plastic housing (no published torque spec — confirm with service manual if available)
9. 9

   Reconnect electrical connector
   Reconnect the electrical connector to the blower motor control module until the locking tab clicks into place. Tug gently on the connector to verify it is fully seated and locked.
10. 10

    Reconnect battery
    Reconnect the negative battery terminal.
    Torque spec

    Battery Terminal Bolts6 Nm (4 lb-ft)

Reassembly

1. Return passenger seat to desired position.
2. Ensure all electrical connections are secure and no tools or fasteners were left in the footwell area.

Verification

• Start the engine and turn on the HVAC system.
• Test all blower motor speed settings (typically 1-4 or low/medium/high depending on trim). Each setting should produce a distinct and consistent airflow.
• Listen for abnormal noises from the blower motor—proper operation should be smooth and relatively quiet at all speeds.
• Verify that the blower motor turns off completely when the control is set to OFF.
• After 5-10 minutes of operation, carefully feel the area around the new module (engine off) to verify it is not excessively hot, which could indicate poor mounting contact.

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

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