Topic

Is there a way to use the PSCAN tool to disable the engine immobilizer? I have a 2000 MG F. The key fob locks and unlocks the doors fine. The immobilizer is the Lucas 5AS. Everything seems to read fine except for the upper seal sensor which reads low. I’m not sure where this sensor is. The horn test was fine. Bottom line is the immobilizer is not disengaging. The EMS code to the ECU seems correct. But the ECU cannot learn the EMS code if the immobilizer is engaged.
This has happened once before. A friend of mine has a Blackbox diagnostic system. With his unit, we were able to somehow reset to factory settings and that resolved the problem. The key fob locked and unlocked the doors, disarmed the alarm and disengaged the immobilizer. That was about four months ago. Now same thing again.
Any advice? Can the PSCAN be used to resolve the problem. Do I have a faulty 5AS unit? I’m in Vancouver, Canada.
Thanks in advance,
Jess

Hi and welcome to the forum

IIRC the 5AS sends a signal to the engine ECU to let the ECU work, it is the 5AS that holds the immobilizer.

James

I believe that there are features in the T4 tool for configuring the 5AS that I have not implemented.
The 5AS was done a long time ago, I think before we had a T4.
It might be time to revisit this but as you can imagine there is a very long list of things to do.
It does sound as though your 5AS has a problem in any case, so it might be a good idea to get a replacement.
As you have a pscan it is possible to do this, you can read the EMS from the old one and program it into a used replacement, and you can code in your fobs too.
To be honest that is probably your quickest solution at this time.

Thanks James and PSCAN. I’ve already ordered a replacement 5AS. I just wanted to make sure that there wasn’t a tool within the PSCAN that could address the issue that I missed.