Hello there, please bear with me as I do my best to describe the situation. On four or five occasions, my car has lost all electrical power. It is not dissimilar to disconnecting the battery: the clock, power windows and memory seat need resetting, the trip computers are reset, and I'm prompted to reset the park brake. This has only happened when I have pressed the start button for shut down or start up. There don't appear to be any trouble codes recorded. I've checked with both a simple OBD2 reader and SDD.

Today the electrical power loss happened as I pressed the start button to start the car. The pressing of the button killed all electrical power. The car was completely dead for at least a minute, and then just returned to life (I love self-repairing cars). For the earlier occurrences, the power loss coincided with pressing the start button for shut down. Today was the first time it happened on start up.

This electrical problem has only been occurring since I had the gear selector module repaired after it had failed. Also of note is that the driver memory seat button now has problems. The number 1 memory button no longer works and when pressing the number 2 button, the system recognises it as the number 1 settings. The seat and steering wheel adjustments all seem to work correctly. I wonder if these issues are related, as the start/stop initiates the steering wheel memory position. FYI - the battery connections are solid. All else seems to be working as it should.

Please, where should I start with diagnosing and trying to fix this problem?

Thanks

 

I have more information on the electrical issue detailed above. The electrical system went completely dead again today upon start up. As in the previous time, the car had been parked in 30+ deg C sun for some time. I pressed the start button, a very short click, and then all dead. I opened the boot with the key to check the battery connections, and upon bridging the negative terminal with the copper extension of the battery monitor with my thumb and fingers to check the connection, the system clicked back into life. Exactly the same thing happened on the previous occasion when I checked the negative terminal connection, but I presumed it was just coincidental. This second time isn't coincidence. Can anyone shed some light on this problem for me?