Internal Control Module RAM Error

P0604 = Internal RAM fault in the PCM. On older Chrysler products this can sometimes be cleared with a PCM reset (disconnect the battery for 30 minutes and cycle the key). If it returns, the PCM is failing internally and needs replacement + programming. Your dealer can confirm whether an open service bulletin or warranty extension applies to your VIN. Note: this module must be programmed to your VIN before the car will run. A generic parts search returns blank or donor units, so order it through a dealer or a rebuilder that programs to your VIN, or have a shop flash it after installation.

Nissan P0604 means the ECM's internal RAM has failed self-check. These ECMs sometimes recover with a battery reset, but a recurring P0604 means the ECM should be replaced and VIN-programmed. Nissan CONSULT III Plus is required for replacement programming. Keep the old ECM until the new one is confirmed working -- some shops will reflash the original. Note: this module must be programmed to your VIN before the car will run. A generic parts search returns blank or donor units, so order it through a dealer or a rebuilder that programs to your VIN, or have a shop flash it after installation.

J-series V6 P0604 is usually an ECM internal fault after a voltage spike (jumpstart gone wrong, welding on the vehicle, etc.). The ECM under the passenger floor gets water damage from clogged A/C drain tubes. Dry the ECM, check for corrosion on the pins, and reseat the connectors. If the fault persists, the ECM needs replacement + immobilizer rematching at a dealer. Note: this module must be programmed to your VIN before the car will run. A generic parts search returns blank or donor units, so order it through a dealer or a rebuilder that programs to your VIN, or have a shop flash it after installation.