Trans failsafe prog

[weirdfish]

Got the dreaded trans failsafe prog coming up, car not used very much so thought it might have been a low battery, but after charging for a couple of days and reading 12.6v still the same.
I can clear it and drive up and down the road but as soon as I engage Park it comes back on, any pointers.

[X5Sport]

Could be the Park function isn’t being seen as engaging/disengaging correctly by the EGS module so it throws a wobbly warning light. There are at least three error codes associated with that and a code read should confirm given a warning has been triggered. BMW error codes 507 B, C or D apparently. All are connected with the parking gear engage, disengage or ‘implausible’ from what I can find on line. I can;t find one specific to the E53, just a list of possibles for a number of models.

[marti]

It may be down to the low battery voltage you had, disconnect the battery for half an hour...neg off first and back on last...

[weirdfish]

That’s what I thought, I have charged the battery and cleared the code but it came back again

[X5Sport]

Just a thought... what’s the voltage with the engine running at fast idle? Does it drop much at idle. I’m just wondering if the slternator volts are dropping to a point that upsets the computers. Poor battery is the usual trigger as we know.

12.6V at rest is an 80% good battery, hence wondering if the alternator volts go a bit low for some reason.

[weirdfish]

Popped it into a local specialist this morning, would you believe it didn’t do it when I parked it in his compound.
Left it with him anyway just to check it over. Will update with his findings.