[toedrag22]

Recently bought a 2002 540i M Sport and had been contemplating doing the AT drain and fill with filter/gasket replacement. Well yesterday, Trans Failsafe Prog popped up, but she didn't go into limp mode though and I could cycle through the gears. I eased it home and parked it. Later in the day, started it back up and no Trans failsafe prog message. Then this morning, back on, but again not into limp mode.

From what I've been reading today, I'm wondering if this seems more to do with the battery/alternator, than the actual trans? Has anyone else had the error message pop up but the car seemed to drive fine? What was the result?

With right at 230,000kms, I'm still planning the drain and fill. Need to find the best alternative fluid in town, as BMW quoted $50/L!!

 

[cdawg246]

Pretty sure it's just a weak battery - I had the same message pop up after a really cold night and not driving my 540i for over a week with the alarm armed. I put the trickle charger overnight on the battery and haven't seen that message pop up again. But I did notice that the auto transmission was slugglish shifting right after the error code was triggered. By the way my duralast red is still going strong going on 7 yrs old.

 

[Flounderasu]

Recently bought a 2002 540i M Sport and had been contemplating doing the AT drain and fill with filter/gasket replacement. Well yesterday, Trans Failsafe Prog popped up, but she didn't go into limp mode though and I could cycle through the gears. I eased it home and parked it. Later in the day, started it back up and no Trans failsafe prog message. Then this morning, back on, but again not into limp mode.

From what I've been reading today, I'm wondering if this seems more to do with the battery/alternator, than the actual trans? Has anyone else had the error message pop up but the car seemed to drive fine? What was the result?

With right at 230,000kms, I'm still planning the drain and fill. Need to find the best alternative fluid in town, as BMW quoted $50/L!!

Maybe post your readings at rest, from the terminals, and running?

 

[toedrag22]

At rest: 12.5 V
Cold Crank: 10.5 V
Running: ran between 13.5-14.5 V, fluctuated with engine idling revs