LED Bulbs - Trans FailSafe
 

LOL, do you believe in coincidences.

I currently do have the upper reds of one of the rears unplugged (socket not working). All other red tail areas and backup installed this morning. Just before I left for work..

Anyhow, wifey texts me. trans failsafe - went into limp. She restarted. No trans failsafe error but for sure, still in limp.

Coincidence or not ;-)
Alter was swapped 38 months ago.

Mine has done that twice in its lifetime. I shut it down for 5 minutes and restart and everything is fine after that. Not sure what to advise you on other than that. :dunno:

Oh, I've had it more than a couple times for sure

Couple times = new trans.

18 months after new trans, it was due to the trans temp sensor. New wire harness resolved

I can't remember but when the gas pedal went bad, it triggered that as well or CEL. Anyhow, for sure it went into limp mode too.

How old is the battery? And which brand Alternator?

The harness change out is an indicator the plug/socket at the transmission is contaminated. Take it apart and apply plenty of electrical contact cleaner, then lube up with dielectric grease before reassembly. I suspect your winter road conditions there have contributed to the situation.


2002 X5 3.0 351,800 miles
2014 428i 44,000 miles


2004 325i sold at 123,600 miles
2001 325i sold at 66,000 miles


1970 Firebird Under restoration

+1 on the trans socket. It tastes very little time to can just drive into a couple bricks to raise one side of the car for a little more room I did mine without lifting the car. I was getting all sorts of trans errors and it was water in the connector


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38 months to the date new batt/alternator.....
Pretty sure it would have been a Bosch Reman.
They are all *reman*, aka, OE vs OEM

Post#5 - the trans harness/wire/temp sensor was changed out many many moons ago. It's been fine since. Truck has been solid with the only ~change ~ was messing with bulbs this morning and coincidentally the trans safe.

Going to see how the battery looks on the MM after a sleep overnight.

All you need is the bat voltage to dip to get a trans failsafe. When in doubt run the hidden menu voltage and make sure you don't get dips below 13 ever especially when going from on to off throttle to coast into a stop.

- Got home, MM on battery. 12.1
- Cranked just fine, took it for a drive around the block - I know, not really good as a alternator test. Anyhow, 13.3-13.6
- Grabbed my standby battery. AGM. On trickle charger every now and then. I though this battery was in good shape. Before swapping batteries, measure V on it. Last time trickle charged was about 2 weeks ago. Dang standby battery was reading 12.2. It's a 3-4 oldish AGM that's get's trickled charges. I've never really measured the V on this - while in storage/and of when off trickle charger. I do know a healthy AGM of this one generally will hover around 12.8+

Anyhow, swapped batteries. Took existing battery and decided to just bench charge it, let it rest and see how it looks in the morning. AFAIK, no alt. lights on the cluster - not that that alt cluster error light always comes in - last alt job, I don't recall it every triggering on the cluster.

Regardless, if the ALT was healthy, even with a bad battery, voltages should not have dipped ? aka, I suppose it's possible the current was more than the alt and V dipped when it needed battery juice , which triggered the trans safe ?

Baby steps I suppose.

And as luck goes, I'm on month 38 out of a 36 month warranty battery :confused::confused:

Indeed it's the alt. Battery rested, holds at 12.7. Took a drive with the test battery. Seems to dip @ stop signs. No trans FS on cluster but she's driving like in limp mode. I have to google to see if it will need to be cleared to get it out. I'm losing my memory as the years go by !