Is there no PCM communication, no crank with key?

Since I have had a no PCM communication, no crank with key, no fuel pump with key. I can crank the engine by jumping the solenoid and fuel pump works when jumping over the relay. I have had two different PCM’s preprogrammed to my vin and just replaced the engine harness that goes to all sensors, FICM, and PCM.

Can you crank an’04 6.0 with no fuel pump?

Please help me. 6.0 no PCM communication, no crank, no fuel pump. … I have an ’04 6.0 that shut off going down the road. Since I have had a no PCM communication, no crank with key, no fuel pump with key. I can crank the engine by jumping the solenoid and fuel pump works when jumping over the relay.

Why is the PCM not communicating with the CJB?

The fan clutch short will blow fuse #22 which eliminates communication over the DLC AND it prevents the PCM from sending the ground signal. You have proven that the ground signal from the PCM is making it to the CJB. Different situation for you, but I wish you well in your hunt.

Can a PCM be damaged in a 2006 truck?

IMO you need to plan on getting a new main engine harness, (and also IMO) it supports trying a known good PCM (which you have in your 2006 truck). The only risk is that you don’t know how that truck is wired now and there may be a slim chance that a known good PCM could be damaged if the wiring was bad.

What does no start no crank no click mean?

If you have a late model GM vehicle and turn the key only to hear nothing, you’ll most likely think you have a dead battery—and you may. But a no start, no crank, no click condition can be far more involved than that. In the old days, power flowed through the ignition switch and down to the starter solenoid. Not anymore.

Is the ignition switch part of the PCM?

The ignition switch now talks to the body control module (BCM) and it’s the BCM that initiates one of two relays. The second relay, the more important of the two, is controlled by the powertrain control module (PCM).

Do you need a PCM for a GM car?

Depending on the year, model and engine of your GM vehicle, your starting system may be less complicated or use only some of the components shown here. For example, earlier anti-theft systems didn’t communicate the same way with the PCM. The bottom line is you MUST get the wiring diagram for your particular vehicle.

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 swapped with a Pats module?

Just swapping out the PCM and using the ‘original’ key from the ‘replaced’ PCM without reprogramming the ‘new’ PCM won’t enable the PATs feature. I believe 1998 and newer fords with PATS used PATSII system in which the key memory was stored in the PCM itself and not within a separate module .

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.

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