745 warning lights

[dave7108]

My 2004 745 seems to be going a bit mental. Occasionally i have the sat nav flickering then Control systems failure. Transmission fault and tyre pressure warning failed. The car still drives but goes in a limp home mode also the power steering fails. If i turn it off wait couple mins and restart its all back to normal. Seems more of an electrical issue?

[Prinny]

How old/good condition is the battery? BMW love to make the car do all sorts of electrical shenanigans if the battery is even slightly low on charge. I’d make that the first check you do.

[Speed addicted]

I'd agree with the battery comment, or the main cable coming off the battery can also fail giving voltage issues.
My 645 did all sorts of weird when the battery was failing, new one sorted everything back out.

Be aware that you need to code the new battery to the car.

[Kewy]

That's alot of warning lights, take it back.

[dave7108]

had issues about a year ago when it was hot (been out for a drive 30 mins etc) ud turn it off and say fill up with petrol then it wouldnt start till it cooled down. So after checking the net I changed the battery but while the hot restarts are slightly better im now getting all this crap with warning lights.

[trickywoo]

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

[Hashtaggggg]

trickywoo said:

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

I have just been quoted £65.00 +VAt to have my E60 545i alternator to be reconditioned

[trickywoo]

Hashtaggggg said:

I have just been quoted £65.00 +VAt to have my E60 545i alternator to be reconditioned

That is an epically cheap price.

Just for the craic have a look at what ecp charge for an exchange.

[Hashtaggggg]

trickywoo said:

Hashtaggggg said:

I have just been quoted £65.00 +VAt to have my E60 545i alternator to be reconditioned

That is an epically cheap price.

Just for the craic have a look at what ecp charge for an exchange.

I did, and then started to investigate!

[dave7108]

How did you get to an alternator fault, was this diagnosed? As I dont want to replace it for no reason!

[Hashtaggggg]

dave7108 said:

How did you get to an alternator fault, was this diagnosed? As I dont want to replace it for no reason!

dodgy electrics:

parking sensors

halo lights

etc..


then after 6+ months an iDrive fault intermittently.

Tried a new battery (£120.00) no change. Bought from Costco so I could had have returned it, except a thieving chav nicked it off my drive during my 10 minute test drive.

[dave7108]

trickywoo said:

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

Did you find the engine ran rough before?

[rayyan171]

Number one thing is battery. Then alternators, then wiring looms. Check floor of car/boot for any water ingress, that plays absolute chaos with any car's electrics.

[trickywoo]

dave7108 said:

trickywoo said:

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

Did you find the engine ran rough before?

Yes and it was funny starting but not because of a low battery as such.

I think more accurately it was the rectifier at fault as the case was cracked.

I got an auto electrician to diagnose it but the voltage across the battery when running made it fairly obvious it would yo yo between 14v and 10v. Hence why it was charging the battery enough for it not to flatten over quite a long time.

[Hashtaggggg]

Hashtaggggg said:

trickywoo said:

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

I have just been quoted £65.00 +VAt to have my E60 545i alternator to be reconditioned

Picked the alternator up last week. The chap was very apologetic as it wasn't done in 24 hour as he said it would be and as it needed a second part the cost would be more.

So instead of £78.00 he actually charged me £90.00

[dave7108]

Has this resolved the issue now? I still need to sort mine out.

[parabolica]

trickywoo said:

I had exactly the same with an e60 545i

Turned out to be an alternator fault. Be sitting down when you look for prices on replacement units.

Yup, same here but on my 645Ci.

[naturalaspiration]

This one?

https://m.autodoc.co.uk/valeo/10186310

Deduct £53 for your unit if exchanged.

[Hashtaggggg]

naturalaspiration said:

This one?

https://m.autodoc.co.uk/valeo/10186310

Deduct £53 for your unit if exchanged.

Chapmans in Sheffield. been fixing alternators and starter motors for 60 + years as a family.