Why does my PCM fail every time I replace it?

Why does my PCM fail every time I replace it?

PCMs typically fail for one of two reasons: voltage overloads (often due to a short in a solenoid or actuator circuit) or environmental factors (corrosion, thermal stress or vibration). If the shorted solenoid or actuator isn’t found and repaired, the voltage overload it creates may damage the replacement PCM, too.

What happens if you replace the solenoid on a PCM?

If the shorted solenoid or actuator isn’t found and repaired, the voltage overload it creates may damage the replacement PCM, too. As for environmental factors, water is the main thing to avoid. If water gets inside a PCM, it can short circuits and set up irreversible corrosion that ruins electronic connections.

Can a PCM be installed in the same car?

Many PCMs appear to be exactly the same on the outside (same sized box and connectors) but may be wired or calibrated differently inside. If the wrong PCM is installed in a vehicle, it may run but probably won’t run well. Close enough isn’t good enough when it comes to replacing PCMs. It must be the correct replacement for the application.

How to turn on security light without starting engine?

Turn key to the “ON” position without starting the engine. Security light should turn on and stay on. Turn key to the “ON” position without starting the engine. Security light should turn on and stay on. Turn key to the “ON” position without starting the engine. Security light should turn on and stay on. Turn key to the “OFF” position.

When to replace your PCM ( and when not to )?

The onboard computer is the brains of the engine control system, so when the brain isn’t functioning correctly neither is the engine or anything else that the microprocessor controls – which may include the charging system, transmission, various emission controls and communications with other onboard control modules.

How to replace the Powertrain Control Module ( BCM )?

The Powertrain Control Module (PCM) Before replacing the BCM or PCM, you should first try the 30 minute Re-learn Procedure which is described in the GM Shop Manual. Here it is in it’s entirity. Turn ON the ignition, with the engine OFF. Attempt to start the engine, then release the key to ON (vehicle will not start).

If the shorted solenoid or actuator isn’t found and repaired, the voltage overload it creates may damage the replacement PCM, too. As for environmental factors, water is the main thing to avoid. If water gets inside a PCM, it can short circuits and set up irreversible corrosion that ruins electronic connections.

Where is the PCM located on a car?

Accessibility can be a problem on some vehicles because the PCM is often buried under or behind other components in the instrument panel, climate control system or console. Some are located under a seat and require removing the seat.

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