ECU how much to fix.. or something else wrong.

[X5Andym]

X5Andym

It all started with the starter motor not starting, from time to time, all lit up but no start, after a few attempts all good, car running, had this checked out, new starter motor required not the same original make Bosch but Lucas was available, car was left with no battery power for a few days, when the new starter motor was fitted no crank the car seemed to have gone to sleep.. battery was good.. seemed to be the ECU, are these units available on the open market and at what cost.. any help advice would be great..
my X5 is 4.4 v8 on a 05 plate 41K only.. should not be having these issues..

Thank you...

[X5Sport]

Have you had a full error log download carried out with BMW compatible software/OBD2 reader?

Brand new ECUs were serious money - well over £1k programmed. That isn’t a BMW price either. They can be fixed and that would save you some funds, but you need to be sure it is the ECU at fault first. It could be a problem with the ignition switch, immobiliser, or even they key transponder.

Unfortunately it isn’t the mileage likely to cause issues now, it will be aging of the electronics.

[henrym3]

I would be getting a second opinion sounds like there probably wasn’t anything wrong with the first starter motor, working from time to time was probably just the start of fault that is elsewhere. I’d be amazed if it’s the ECU. Unplug it and see if there’s any corrosion on the pins. If it doesn’t start check that the motor is getting volts. Ignition switch as suggested must be checked first simply because it’s cheap. I’d be reluctant to start throwing parts at it. 41k bloody hell must be in good nick.

[X5Sport]

Thinking about this, it would be well worth checking for a bad earth connection - either loose or corroded. Damp could have got into places simply through lack of use. I don’t recall anyone on here, across all of the models, reporting an ECU failure. They are very rare (you might be unlucky) but there’s lots of other things to investigate first.

Starters were an issue in 2004/5 but that didn’t affect Bosch manufactured units.