Ignition Control Module

This procedure covers removal and replacement of the Ignition Control Module (ICM) on the 2005 Dodge Viper 8.3L V10 engine, including disconnection of ignition coil connectors and proper reinstallation.

Warnings

Tools required

Parts

• Ignition Control Module × 1 — Use OEM specification
• ICM mounting gasket or thermal pad (if equipped) × 1 — Inspect during removal; replace if damaged

Preparation

1. Park vehicle on level surface and engage parking brake
2. Ensure engine is completely cool to the touch
3. Open hood and secure with prop rod
4. Disconnect negative battery terminal using appropriate socket
5. Wait minimum 2 minutes for electrical system capacitors to discharge

Procedure

1. 1

   Locate Ignition Control Module
   The 2005 Viper 8.3L V10 uses a coil-on-plug ignition system controlled directly by the Powertrain Control Module (PCM). Verify whether a discrete Ignition Control Module exists on this vehicle before proceeding; if ignition control is integrated into the PCM, this repair may instead require PCM or individual coil-on-plug service. Confirm component location against factory service documentation. Consult factory service documentation to confirm the presence and exact location of any ignition control module on this vehicle. If ignition control is handled by the PCM, identify and note connector orientations on the relevant component before removal.
2. 2

   Disconnect Ignition Coil Connectors
   Disconnect the electrical connectors from the ignition coils that interface with the ICM. Press the connector release tabs and pull straight off each coil connector. This engine is a V10; verify the exact ignition coil configuration (individual coil-on-plug per cylinder versus coil packs) against factory service documentation before disconnecting connectors. You may need to disconnect multiple coil connectors depending on access requirements to the ICM. Mark or photograph connector positions for reinstallation reference.
3. 3

   Disconnect ICM Electrical Connectors
   Locate the two main electrical connectors on the Ignition Control Module. Press the locking tabs on each connector and pull straight away from the module body. Do not pull on wiring harness; grasp the connector body. Inspect connector pins for corrosion or damage.
4. 4

   Remove ICM Mounting Hardware
   Remove the mounting bolts securing the Ignition Control Module to its bracket or mounting surface. There are typically 2-3 bolts holding the module in place. Use appropriate socket and extension to access bolts. Support the module while removing the final bolt to prevent it from dropping.
5. 5

   Remove Ignition Control Module
   Carefully lift the ICM away from its mounting location. If equipped with a thermal pad or gasket between the module and mounting surface, note its position and condition. Inspect the mounting surface for debris, corrosion, or damage. Clean mounting surface with shop towel if necessary.
6. 6

   Prepare New ICM for Installation
   Inspect the new Ignition Control Module for any shipping damage. Verify connector pin alignment matches the original module. If a thermal pad or gasket was present on the original module, transfer it to the new module or install a new one according to manufacturer specifications. Ensure mounting bolt holes align properly.
7. 7

   Install New Ignition Control Module
   Position the new ICM onto the mounting bracket or surface, aligning mounting bolt holes. Insert mounting bolts and thread by hand to prevent cross-threading. Once all bolts are started, torque them evenly to the manufacturer-specified value (verify exact torque spec in factory service documentation before final tightening).
8. 8

   Reconnect ICM Electrical Connectors
   Reconnect the two main electrical connectors to the Ignition Control Module. Push each connector firmly until the locking tab clicks into place. Tug gently on each connector to verify positive engagement. Apply dielectric grease to connector seals if desired for moisture protection.
9. 9

   Reconnect Ignition Coil Connectors
   Reconnect all ignition coil electrical connectors that were removed in Step 2. Push each connector onto its corresponding coil until it clicks into locked position. Verify each connection is secure by gently pulling on the connector body.
10. 10

    Reconnect Battery and Test
    Reconnect the negative battery terminal (note: the battery on the 2005 Viper is located in the rear/trunk area, not the engine bay) and tighten the terminal clamp securely. Before starting the engine, turn the ignition key to ON position (without cranking) and verify no warning lights remain illuminated on the dashboard related to ignition system. Clear any stored diagnostic codes if applicable using scan tool.

Reassembly

1. Ensure all electrical connections are fully seated and locked
2. Verify ICM mounting bolts are torqued to specification and module is secure
3. Route all wiring harnesses away from hot engine components and moving parts
4. Double-check battery terminal connection is tight before attempting to start engine

Verification

• Start engine and listen for smooth idle without misfires or hesitation
• Allow engine to reach operating temperature and verify no check engine light illumination
• Test drive vehicle under various load conditions to confirm proper ignition timing and engine performance
• Use scan tool to verify no ignition-related diagnostic trouble codes are present
• Verify all ignition coils are firing properly using scan tool live data or oscilloscope if available

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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