My car was at an independent BMW shop....they wanted to replace the trans solenoids when that happened....it took me a day searching and I found the TSB or recall..cant remember...but I had them clean the connector and it worked. I did change the Neutral Switch because that was supposed to be replaced on the TBS..the switch's glue would separate letting moisture in.
The system said when it idled for a prolong time the "trans Prong Fail" would appear and the trans would stick in 3rd...slow to take off then wind out.
Try spraying the shit out of the switch and connectors first, take the connectors apart...that should solve the problem but it will come back when it gets dirty.
I cant find the TSB...it's out there.
Almost anything on these cars will make the "Trans Prong Fail" to come on from wheel bearings, anti-lock brakes, mass air flow, alternator....and so on.
If you can get away with a repair under $1,000 your doing well with this money pit BMW made.
BMW E53 X5 M62 4.4L Drivetrain Automatic Transmission - 24107512755 - Transmission Gear Indicator Switch - ES#44516
I hope the owner before you did the valley pan coolant leak...Valve cover gaskets and timing chain guides replaced. $8k if your lucky to repair ...be aware of this
Oh the radiator and overflow tank will just come apart soon if they haven't already.
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2002 X5 4.4i Sport Wheels
2014 X5 35i M Appearance & suspension package
1995 Porsche 993
1972 Porsche 914-6
2020 GLE 450 Twin Turbo
2019 Alfa Stelvio 500hp Quadrifogilo
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