New battery & Alternator causing Trans. Failsafe Prog

[bcredliner]

Originally Posted by mcfee03

1. Was running OK-ish after the DISA and CCV replacement, but the battery was not charging, indicating a dead alternator.
2. BMW airbag check (see detail below)
3. Replaced alternator, jump started car with OLD battery. Engine drove weak/lights were dimming on/off but NO failsafe error came up...
4. When replacing Alternator, broke the Auxilary Water Pump, bought a replacement
5. Replaced battery, car starts every time but immediately goes to Trans Failsafe

Could it be rejecting the new Auxilary water pump? Do I need to register new parts to the ECU?


*MAY be unrelated* But... I took it to BMW Sydney for the airbag recall check. Drove fine there. When they gave it back to me, it was incredibly weak. I took it back immediately. They used some "powerpack" to jump start it immediately. I would normally leave it on jumper cables for 30 mins then start.



I have not cleaned it with MAF cleaner- but is dust likely to cause this? It is also a bit broken... http://imgur.com/9p3iSPF

No need to let ECU know you have changed aux water pump.

The MAF may or may not be the problem but I would replace it with an OEM part because it is broken. I wouldn't even bother cleaning it. I wouldn't ever take the chance anything could be sucked into the engine.

[Crowz]

I bet they screwed up something.

The old adage are words to live by KIS Keep It Simple.

1.Drove fine to get the airbag swap.

2. Went to hell in a hand basket while they had it.

3. They broke something so make them fix it.

At least hat would normally by the scenario but you have done so much since then who knows.

[blakamin]

Originally Posted by Crowz

I bet they screwed up something.

The old adage are words to live by KIS Keep It Simple.

1.Drove fine to get the airbag swap.

2. Went to hell in a hand basket while they had it.

3. They broke something so make them fix it.

At least hat would normally by the scenario but you have done so much since then who knows.

Except if the alternator was screwed before, and he drove it to BMW, he probably totally effed the battery himself. To the point of draining to near-collapse.

I cooked a battery once driving a car 160 miles with no alternator. Lucky the thing didn't burn



There's too much weird shiz going on with this thing now to diagnose without having a look. I'm sure there's some important info being left out, accidentally of course, but missing none the less.

[blakamin]

When did you take it in for the airbag? Before the alternator (from what I can gather)?

What did BMW say? Surely they said something besides "we jump started it". Did they tell you your alternator was stuffed?
When the Mrs got her airbag replaced, they checked for any other faults. And told her there was none (we also just got an invite to see the new X3 before it goes on sale).
It's weird they didn't take the opportunity to sell you an alternator if they had to jump start your car.

The lights still "dimming" after an alternator swap is really interesting (ignition switch or dodgy alternator?) but I'll leave that up to ignition switch experts.

[mcfee03]

Originally Posted by blakamin

When did you take it in for the airbag? Before the alternator (from what I can gather)?

What did BMW say?

It's weird they didn't take the opportunity to sell you an alternator

Yep, I took it to them before I replaced the alternator. All I had done when I brought the car to them was the CCV, and replaced the DISA. That took me months (waiting on shipping etc) and the battery was dead.

They said the car looked good for its' age, and nothing was outstanding (aside from the dead battery).

I asked the Mastertech, explaining that it doesn't charge, and he attemptedsell me an alternator. I politely declined (and did myself).

Originally Posted by sgrice

If you already are aware of the above, then I apologize and don't mean to sound like a know it all. It's your car, of course - but I'd replace that switch. Not very expensive, and not hard or time consuming.

Thank you! You are not pestering. That is very useful information. Is an OEM ignition switch essential, or will an generic eBay one suffice? I will await BMW's diagnostic before I do this swap.

In light of the comments after I mentioned what happened with my BMW airbag check, I thought I'd call them up.

I politely explained the situation (I brought the car in running fine, aside from a dead battery, and the car they returned to me felt very different). They have agreed to do a "complimentary" diagnostic... Good news?

What information should I give them here? What is crucial for me to ask?


EDIT: Apologies for the delayed replies. Got pretty de-motivated with all this- was so hopeful that I could drive this week. Coming along to 5 months of learning to repair

[andrewwynn]

I use dash commend app. It lets you build a gauge so you can plot voltage over time. If you are getting light blinks the voltage is not stable. If voltage isn't stable can cause any sort of problem.


Did you ever have failed starts to indicate likely ignition switch? Very recently followed a thread where Flakey behavior was the ignition switch

[sgrice]

Mcfee03 - I don't mean to sound like a pest, but I want to make sure you know what is meant by saying to check/replace the ignition switch. Your earlier comment seemed to indicate that you thought that since the car started then the ignition switch must be good. But I want to make sure you realize that the starting of the car is only one small part of what the ignition switch does. Also, by ignition switch we are not talking about the tumbler/cylinder that the key goes into. Instead, the ignition switch we are talking about is a conglomeration of around 10 different relay switches. These relays provide power to lots of different systems (including - ahem - the transmission solenoids). It may even affect the MAF sensor, though I'm not certain. These relays can fail/pit over time and cause all sorts of weird electrical gremlins.

Earlier postings gave links to youtube videos showing how to replace this switch.

If you already are aware of the above, then I apologize and don't mean to sound like a know it all. It's your car, of course - but I'd replace that switch. Not very expensive, and not hard or time consuming.

Good luck.

[mcfee03]

Originally Posted by sgrice

Mcfee03 - I don't mean to sound like a pest, but I want to make sure you know what is meant by saying to check/replace the ignition switch.

Is it still worth me getting the ignition switch?

I asked the indy to check it. He said no, because the MAF sensor he's saying is the cause.

[bcredliner]

Be sure the service advisor understands the symptoms clearly so technician gets good input for diagnostics, minimize anything lost in translation.

Diagnostic are not always conclusive so don't be surprised if advisor contacts you about the cost of tests that need to be done to pinpoint the problem.

Wait at the dealership if you can.

[upallnight]

Get a print out. Don't just talk to the tech. You will not remember everything that the tech tried to explain to you.