Why are bi-directional controls temporary?
GM built in safeguards to prevent bidirectional controls from corrupting or permanently altering the programmed calibrations. One such safeguard is that the PCM requires the scan tool to send a “keep alive” message to the PCM every 5 seconds. If the next “keep alive” message is not received within 5 seconds of the previous one, then the PCM automatically terminates ALL bidirectional control settings and returns control to the programmed calibrations. That means whenever EFILive is unplugged or the vehicle’s ignition is switched off, the PCM will always return to it’s programmed calibrations.