Starts then turns off security light comes on
- Thread starter Johnstephens91
- Start date
Can you say with some certainty exactly when the security light turns on?? Is it at the moment you turn the key from RUN to CRANK, or does the light turn on a little later, maybe after the engine starts??
It might be a significant difference.
When the key is turned from RUN to CRANK a small sensor inside the lock mechanism is supposed to send a signal to the BCM,, and the BCM sees this signal and sends a message to the PCM that says it is OK to start the engine.
After the engine starts, the PCM is supposed to send another message back to the BCM that is often called a "fuel continue password" or something like that. If this fuel password isn't right the BCM tells the PCM to disable the fuel delivery.
It sounds like your truck is starting but then dying due to fuel cutoff, is this right??
Did this just begin out of the blue or was there some recent work done. Any work at all, even if it seems unrelated?
