E39 Trans Failsafe Prog

[Jamex316 1]

Guys, my e39 went into failsafe mode in yesterday after driving to Auckland.

The workshop says something about a need for transmission overhaul due to worn clutch or something to that effect. What should I do?

He has reset the car and drives fine but its obviously going to pop right back again later.

[hybrid 1043]

Define 'fail-safe' ? There a couple of things that could mean both completely different.

[matt45 1]

Would be interesting to know what they did to come to the conclusion that it needed to be overhauled. The failsafe can be caused by heaps of things eg. Bad battery/alternator.

[hybrid 1043]

Could be anything, Another one is the auto trans fluid over heating because the 'heat exchanger' attached the bottom of the radiator is poked. Once the gear box temp gets above a certain level the EGS holds gears all the way up till 4000rpm before changing and also the changes are quite rough or abrupt. It settles down when a bit of air flow over the radiator happens for around 5-10mins. There are two - three stages before it throws a full spaz. Starting and stopping the car does work either, only letting the gearbox fluid cool down. This is the EGS's last line of defense against over heated trans fluid.

Anyways, thats what a lot of people confuse limp mode being .. There are others.

[Jamex316 1]

I wasn't there when they checked the car, they supposedly plugged the car to the computer and read the error code from there. After reading some posts, I agree with the opinion that many things could bring up that warning.

Anyways, the failsafe program basically put the car into limp mode so I was unable to drive the car at normal speed.

I guess its now too late to go back and read the car again after they have reset the computer right?

[Jamex316 1]

Would be interesting to know what they did to come to the conclusion that it needed to be overhauled. The failsafe can be caused by heaps of things eg. Bad battery/alternator.

The dashboard read "trans failsafe prog" so I don't think its a bad battery or alternator.

[hybrid 1043]

are you sure ?

What error codes did the mechanic come back with ? What actually happened when it went into 'fail safe' mode ?

[matt45 1]

The dashboard read "trans failsafe prog" so I don't think its a bad battery or alternator.

Bad battery/alternator = dirty/low power

dirty/low power = computer going abit french

computer going abit french = surrender

but yea could be heaps of things, needs to be check by someone who knows what they are doing not just a Muppet with the ability to read fault/error codes.

[Jamex316 1]

I've checked the battery, it seems to be showing black meaning the battery has insufficient charge.

If it is the battery, then the workshop guy was dodgy in saying the transmission needs an overhaul.

But just because the battery is going bad, it doesn't warrant the car being put into limp mode does it?

I haven't had trouble starting or anything...and the battery is reading out 12.4v.

I wasn't there when the guy checked it on the pc, so don't know what error codes came up, and he reset the whole thing so basically I'm not able to find out what actually happened.....

Only thing I know is, the car was idling after I drove up to akl from ham, and the failsafe kicked in while the engine was still running. The car was idling for quite some time while I was waiting for a car park (15mins), so initially I thought it might be the transmission oil overheating or something. But if its the battery, would the failsafe kick in while the engine is still running?

[hybrid 1043]

I would go somewhere were they have experience in such things EG BMW specialist shop.

I'm not point fingers at mechanics but most in NZ are use to fixing you run of the mill mazda or toyota and things like voltage drop or other causes dont really factor into their diagnositic work because they just dont know or have lack of experience in such things.

The e39 really is a driving computer system.

[*Glenn* 854]

If the alternator under or overcharges it can cause many problems in late model BMW's. Overcharging does the most damage. The OP should get it checked as suggested by a Dealer or BMW specialist

[Jamex316 1]

Yeah, the guy at the workshop was probably using the "trans" part of the term to fool me into thinking that the transmission is faulty. Can I reset the failsafe by unplugging the battery?

I've checked the battery voltage, its 14v while engine is running and 12.4v with the engine off. The green indicator on the battery suggest the battery is ok.

Will the bmw dealship pick up what was wrong now, after the whole thing has been reset?

[*Glenn* 854]

The OP should get it checked as suggested by a Dealer or BMW specialist

Bump

[matt45 1]

Will the bmw dealship pick up what was wrong now, after the whole thing has been reset?

If it is still in failsafe then definatly they can see codes, if the codes were cleared and its no longer in failsafe there may or maynot be codes that have been logged scince (lots of errors are logged that dont come up on the display).

Regardless if you are having issues with it take to a BMW workshop.

[Jamex316 1]

Can someone explain the heat exchanger causing overheating? Cos I suspect that is what is happening.

There was smoke today after driving to akl today. Car is fine while moving, as soon as the car is stationary, I can smell heated fluid.

[*Glenn* 854]

At least 3 of us have given you the right advice... why don't you listen ??

GET IT CHECKED BY THE DEALER OR A BMW SPECIALIST

[Jamex316 1]

I am taking it to bmw today, just want to know more about it.

[Tristan 338]

I had this. Took it to dealer. New alternator and regulator.

That was easy, wasn't it?

Edit:

Cry more, my computer's powered by children's tears.

Edited May 6, 2011 by Help

[John McGregor 0]

If it is still in failsafe then definatly they can see codes, if the codes were cleared and its no longer in failsafe there may or maynot be codes that have been logged scince (lots of errors are logged that dont come up on the display).

Regardless if you are having issues with it take to a BMW workshop.

If the failsafe warning comes on after a short period of driving and then goes away after the engine has cooled down it is being caused by the ABS ecu being overheated by the adjacent exhaust manifold. This happened on mine and I wrapped the ABS in foil coated fibreglass for insulation and so far the problem hasn't come back.

[hybrid 1043]

That's one of many reasons. Yours is probably a cracked circuit board in the ABS pump control module in your case. http://www.magnum1.com/magnum/BMW-740/740_...-Repair-740.php

Scanning the car will reveal some clues, but not always the issue. As Glenn says it take someone with some understanding to work it out. You can actually work it out for yourself, it just gets harder when you don't have components to swap out and test.