`07 530D: Autobox trip out

[dannyboy201062]

Hi All, I have an `07 530D with an intermittent auto box trip out issue. It doesn`t happen
with my wife who drives it mostly on 10 mile runs , but happens when I drive it on long runs.
You can be in the fast lane on the Motorway and suddenly the revs shoot up accompanied with “Gearbox Failure “ message and I think the gearbox defaults to 3^rd gear.....hard to know , usually you are trying to get the the hard shoulder ASAP where an off/ on on the ignition switch and all is normal again. The fault codes prodused by this are typically as follows:

EGS Transmission mgmt:
51AA ( Not present ) Incorrect signal from GWS: position info.
CF2E ( Not present) Location data ( LIN ) from GWS.
4F83 Ratio monitoring from clutch C.
4F85 Ratio monitoring from clutch E.

ABS-DSC Dynamic stability control premium:
6E62 ( Not present) DSC Brake-air flap plausibility.
D37D ( Not Present ) Message ( FZD/rain/light sensor Ox226 missing,receiver DSC transmitter rain/ light sensor.

The car does have a rain sensor issue so not worried about that one . I have read somewhere on the forum that an over voltage situation can cause these types of issues. The voltage does seem high as follows:
Did a voltage check on a long run ( 1.5 hrs ) . Battery is about 12.8V before starting, drops down to approx 9V during turnover, engine spins over normally and starts easily, volts return to 12.8V then rise to 14.8V for approx 20 min and then stay at 14.2V until shutdown. Volts then return to 12.8V. Checked fault codes and the “ 6E62 ( Not present) DSC Brake-air flap plausibility” had reappeared. Cleared that again.

To me it sounds like an electrical glitch due higher than should be charging voltage and I am considering replacing the voltage regulator ( on the alternator ? ) need to do some research on that before attempting. Any advice appreciated. .................regards....Dannyboy

[iregj]

The voltage is fine, why do you think it is high?
Looks like gearbox problems.