OEM 2004 Chevrolet Classic Engine Control Module

2004 Chevrolet Classic Engine Control Module Parts and Q&A

• Q: How to replace the Engine Control Module (ECM) on 2004 Chevrolet Classic?

  A: Disconnect or reconnect the pcm connector only when the ignition is off because doing so without power allows internal damage to occur. The process starts by disconnecting the negative Battery Cable before taking off the left closeout/insulator panel. The pins on the pcm connector along with soldered components must be protected from electrostatic discharge through avoidance of touching them to prevent failure. Also avoid removing integrated circuit boards from their carrier. The pcm harness connectors need disconnection by using a thumb to push down the locking tab and pull up the release lever. Use a finger to make the pcm retaining tab depression while sliding the pcm unit upward and out of the pcm bracket. The new pcm requires inspection to verify its service number matches the one from the defective unit. Bolt the new pcm into position through the bracket while allowing the retaining tab to produce a locking connection before installing the pcm connectors and securing all release levers. Put back the left closeout/insulator panel and then close the negative Battery Cable terminal. The replacement pcm needs reprogramming while the maintenance of crankshaft position (CKP) system variation learn process should happen immediately. The service programming system (SPS) should be used to program the existing pcm.