car gone into total meltdown - battery, alternator, regulator, CPU or something else?

[Upex]

All,

My S320 CDI (01 w220 pre face lift) was showing signs of a fading battery, so ordered a new one with higher ah and cca that arrived yesterday and was waiting for me when I got home.

Wire drive car off to work this morning, to ring me from 5 mins down the road having had the low voltage, bas, pas, airmatic (etc) warnings come up.

What luck I though, new battery just arrived, so I pop out and fit it. Car starts and the lock to lock steering method clears all the errors. I then went to work thinking all was well.

Gets a call from wife on her way home, car has done the same thing on her return leg but on the new battery this time and having done 20-30 miles fine. I dash out to find that the car won't even try to turn over.

I had to use the old battery that I removed in the morning to just get it started. Once running, all errors were back and lock to lock wouldn't clear them. Also, there were more errors including coolant, distronic, faulty display and maybe some others that I didn't catch and literally nothing worked, Windows moves a cm very slowly then stopped, no indicators, no Speedo, the whole dash blacked out, no headlights.

Left her run for 10 mins, and still no joy. Trying the lock to lock was very heavy on steering and when got to the locks, it's like they weren't there, just got stiffer and stiffer as I got closer to the ends, but no definitive stop as such.

After a little while I was able to get the very dim headlights on to limp her home. During this drive there was literally no go in her, 3k revs to even start to move off, very very slowly. No power anything, brakes, steering etc and she couldn't reverse 1 foot, just moved a couple of inches and stoped. I had to push back on the drive, which came just in time as the suspension had dropped to rock bottom then.

Does anyone have any idea on what's wrong or on how I can start to trouble shoot?

I did put a volt meter across the new battery when she was running and it showed about 7.3 volts (that was with the new battery but post stranding) but having taken the new battery out once home, it's at 10+v

Please help,

Upex

 

[Ted]

It sounds very much like the car isn't charging.
The best advice I can give is to charge the battery and get it to a good auto electrician or an indy with star.

 

[Upex]

That was my thought Ted, but don't know of one, so may need to be stealer in Norwich. Would a lack of charge/battery juice cause the massive loss of drive and total loss of reverse as that's scared me most.

 

[claggy001]

That was my thought Ted, but don't know of one, so may need to be stealer in Norwich. Would a lack of charge/battery juice cause the massive loss of drive and total loss of reverse as that's scared me most.

Hi Upex,
Can thoroughly recommend Alex Crow - he's based in Stowmarket but I consider it well worth the 140 mile round trip from here. He's quite a bit closer to you.
Hope you get it sorted.

 

[Ted]

Upex, at the voltages you are quoting I think that would be extremely likely.
Best looked at by someone who really knows what they are doing, but sounds like alternator or voltage reg.
Have you checked the drive belt?

 

[jaymanek]

A Seized pulley must have sheared the poly v belt hence you have no power steering. Maybe alternator pulley maybe one of the others..

 

[Upex]

Claggy, thanks, will note that for future work, but like this, if need 4-5 full batteries to stand a chance of getting there lol, and that's if a full battery brings back the drive (power).

The serp drive belt I presume Ted, on the front? If so, looks ok from what I can see and was replaced about 12-18 months or so (by a pro, not me lol) as I sprung a diesel leak and it got soaked, so was replaced once the leak was fixed.

If looking down from front of car, is the alternator on the right side, towards the front? If not, any idea where (and likewise for the voltage regulator?)

Thanks,

 

[Upex]

Jay, you mean the big serp belt on the front to? As looks ok to me, but will look more closely when try the charged battery - taking hours lol

 

[Ted]

I'm afraid I can't help with the alternator (other than at the front of the engine!) location but the voltage regulator will be a small black box screwed to the back of it. These are generally the most likely component to fail.

 

[AMGeed]

Jay, you mean the big serp belt on the front to? As looks ok to me, but will look more closely when try the charged battery - taking hours lol

If the battery was totally flattened it needs at least 12hrs charge at high 6/8amps to bring it back.

 

[Upex]

If the battery was totally flattened it needs at least 12hrs charge at high 6/8amps to bring it back.

Well I assume it was pan flat due to the issues, and was 10v once home, but was new this morning lol. I'll leave it in charge overnight, as it only went on charge at 6 this pm.

If the fully charged new battery starts the car and brings the car back to life tomorrow morning, I'll try and run to work in it, but with a spare battery in boot (as have a smaller one that was new yesterday to (for the wife's car). If it does again, is it ok to run the smaller battery via jump leads to the bigger one to limp home, or will that kill the smaller battery to? Keen to not get stranded like today, but equally need to get to work somehow.

 

[jazzyglobe]

Agree with Jaymanek^^.

Sounds like an issue with drive belt/pulley somewhere. Alternator not getting enough drive through the belt to keep charge up. Power steering is through the same belt which runs the power steering pump. I would remove the belt, inspect for damage to belt, spin pulleys by hand, check for worn bearings/noise, fit a new belt and tensioner, then take it from there.

Could be regulator failing in alternator, but I would check belt first as above.

 

[jazzyglobe]

I wouldn't drive it much at all until checked out.

 

[Upex]

Thanks jazzy.

If the full battery restores everything (if only for a short while) including the power steering, then could one assume the belt is less likely and that the alternator or regulator are more likely culprits? Obviously if power steering doesn't return, the belt and tensioner are even more likely?

Just trying to help my understanding/troubleshooting in general, not trying to second guess anyone. Might as well try and learn through this pickle lol.

Cheers,

 

[Upex]

Well, 12hrs of charge on the new battery, reinstalled and all well. Everything back to life and the car pumped up of the floor.

Tested the voltage across the battery poles after a little drive and with engine running, 11.74v, so it's not charging (I think given above replies).

Took off the engine covers and had a good look (as best I could) at the serp drive belt and it all looks fine. With engine on, the alternator pully wheel thing is spinning nicely, doesn't sound rough, the belt isn't jumping or slipping that I can see and the power steering was fine.

From this, is it more likely to be the alternator itself or the regulator on the back of it, rather than belt?

If so, is there any way to easily find out which? As im dubious to try and get it to garage before knowing (as far as possible) what's wrong, to find that they don't have the bit and I'm stuck etc. Equally, having had some silly quotes for bearings in the wife's car, I don't want to be conned into a new alternator and reg. If it's just the reg etc.

Are the two separate though? Or does they come as a pair? Is it a diy job to change, or shop job and roughly how much price wise (recent quotes have made me cautious).

Cheers all,

Upex

 

[AMGeed]

I don't want to be conned into a new alternator and reg. If it's just the reg etc.

Are the two separate though? Or does they come as a pair? Is it a diy job to change, or shop job and roughly how much price wise (recent quotes have made me cautious).

Cheers all,

Upex

This thread shows how the regulator is separated from the alternator.
http://www.mbclub.co.uk/forums/general-discussion/185342-stubborn-damaged-screws.html

Can't help with diagnosis or price but the OP of the thread I mentioned may see this and let you know.

Edit.I see you have enough posts to send a PM. Maybe send a message asking prices.

 

[grober]

Ask around locally for the name of a good independant vehicle electrician/firm . They will charge far less than MB to fix your problem. Could be the alternator or its diode pack or the regulator brushes assembly. Usually refurbed alternators can be bought through an exchange service. You pay the full price and then get an agreed allowance back for the old one when you trade it in- can defray the cost considerably. If the alternator is easy to get at - usually release the belt + undo 2/3 bolts and swap em over- then that keeps labour costs down too. There's always a danger about throwing DIY money at a problem of course and why its sometimes better leaving thing to the pros. SOME electrical problems can for example be traced back to something simple like a faulty engine earth strap.. These things are not termed electrical "CIRCUITS" for nothing.

 

[Ted]

It's pretty much impossible to test an alternator separately to the regulator (and vice versa) as the two effectively make up the one unit (however overcharging is a symptom of a faulty regulator)
Grober has given the best advice - time now to get the experts to take a look.

 

[Upex]

Well limped to garage today that's by work and they say it's the alternator. £539 for a new Bosch unit, fitted, with a coolant change. Seem reasonable?

Chap said it was 2 hour job, and I asked for coolant change, as needed it anyway, and would lose some during the alt change.

Thanks all, not the result I wanted, but least should be sorted on Monday.

 

[grober]

Right-it would appear you have a water cooled alternator- these are much harder to work on than the old aircooled type where you had ready access to the regulator/brush pack at the rear of the unit. You could sometimes renew these in situ if there was enough room.
Here's an example of a water cooled regulator on a BMW but removal is basically similar.
[YOUTUBE HD]K21y1NQSb2w[/YOUTUBE HD]

then regulator change as follows
[YOUTUBE HD]4rjdKgX-pVk[/YOUTUBE HD]


For these because of the work involved I would suggest it makes a lot more sense to renew the alternator with a new or exchange unit as you appear to be doing.