Fault warning message what does this mean?

[paul c]

Wilst traveling in slow moving traffic i got warning message Undervoltage cosumer defective with picture of battery pressed button on wheel it dis appeared than drove another 100mls no problems got home did acheck it says
no malfunction on checking manual it does not explain what this means but tells me it is a cat1 fault any ideas? whats my next more if any?

 

[jberks]

As the message says, the voltage in your electrical system was low so rather than let it get worse and cause a breakdown, your car is clever enough to start switching things off to save power. As the battery recovers, the message goes away. Not sure what it turns off as when we've seen it, normally everything seems to be working fine.

The fix is
a) Get the charging rate checked to rule out the alternator.
b) If all ok, and the battery is >3 years old - replace it as a precautionary measure. (£50-£100)
c) If the message returns - you on the hunt for a battery draining fault.

Sadly C is all too common but you need to rule out a and b first.

 

[television]

As JBerks but if the car has not been used much or only on very short journeys why not try a good charge.

On my SL I have to charge the battery every 6 weeks to keep the message away.

Crawling in traffic with wipers heating radio and all the rest can cause this

 

[paul c]

Thanks for replies battery is fairly recent so will have to try the other options

 

[television]

To be truthful alternators either work or they do not, if it was not working the lamp would be on,, I still say charge it up

 

[paul c]

Have been to the stealership they tell me the alternator is not chargeing enough price to fix is £562 inc vbelt i am not happy:-x

 

[television]

Go to a Bosch service center and ask them, they do re conned alternators,,it may only be the brush pack on the end £10

 

[jberks]

As Malcolm say - worth a charge up first.
It may not be quite up to offical spec but it may still be fine for normal use so don't jump at replacing it. I dare say if I went in with that warning a dealer would tell me the same thing as after 50k or so it's not going to be perfect. Works perfectly well for me though.

A dealer told me the starter needed replacing on our 3 year old 3 series. It was drawing too much current. We sold the car 10 years later...never touched the starter.

I'd charge the battery and see how it goes and maybe get a back street auto electrical shop to check the charging rate. They're likely to be less 'utopian'. If they say it's shot, then off to Bosch.

 

[Splatt]

Food for thought HERE;- http://www.misterfixit.com/alterntr.htm

It appears that an alternator has several sets of windings, each with it`s diode. If any winding or any diode fails the alternator output is
reduced.
I do remember a few years back giving a driver with flat battery a jump start. It was an old Morris minor and it did not occur to me to check if the battery was negative earth, it was not and I blew the lot. However it also blew the charging warning light and it was not till I got 200miles up the M1 and ran out of battery that the problem became manifest.

 

[television]

Food for thought HERE;- http://www.misterfixit.com/alterntr.htm

It appears that an alternator has several sets of windings, each with it`s diode. If any winding or any diode fails the alternator output is reduced.

The red warning lamp will light in one of 3 ways in there was a diode fault,, the car also runs on the alternator and not the battery.

The other thing is that the battery cannot be checked for charge on an unknown battery state

 

[paul c]

Have just been to Bosch they ran a test and tell me the alternator is lazy and probably this
is why i get the message but they cant look at the bushes without taking it apart battery is fine but alternator would be fine for a Ford van but maybe not for mine because theres lots running of it.

 

[television]

Then I say give it a good charge and see how it goes

 

[Splatt]

The red warning lamp will light in one of 3 ways in there was a diode fault,, the car also runs on the alternator and not the battery.

If the Alternator fails the car will continue running on the battery untill the battery runs low.

 

[paul c]

Thanks for the advice will give it a good charge and see how it goes, do you think that price is okay or would a recon from Bocsh be a lot cheaper they could not give me a price without having it in checking serial numbers etc etc merc price is inc 20% discount on labour and 7% on alternator .

 

[jberks]

Certainly go for a recon if you can. A lot cheaper and no difference in what you end up with. See what Bosch would charge you for a recon unit or to recon yours before deciding. Also there are a lot of local reconditioners so worth making a few phone calls. I once got new bearings fitted to a heavy duty alternator (ford student car) whilst I hung about in the repairers car park and I got change from £20. Ford wanted a couple of hundred for an exchange unit.

 

[television]

Certainly go for a recon if you can. A lot cheaper and no difference in what you end up with. See what Bosch would charge you for a recon unit or to recon yours before deciding. Also there are a lot of local reconditioners so worth making a few phone calls. I once got new bearings fitted to a heavy duty alternator (ford student car) whilst I hung about in the repairers car park and I got change from £20. Ford wanted a couple of hundred for an exchange unit.

Definitely as the above if you do need one

 

[paul c]

Thanks for the sage advice car is on the charger will keep my fingers crossed and see how it goes

 

[paul c]

Tried that fix sad to say it only lasted a day then red warning came on car started to shut down everything abs and esp, had to have new alternator.

 

[television]

Tried that fix sad to say it only lasted a day then red warning came on car started to shut down everything abs and esp, had to have new alternator.

Its much cheaper to go to Bosch service center they are ½ the price of MB and also do recon units where as MB do not, unless or coarse your battery has a dead cell that would give the same effect, a good battery place can test that, the best place again is the Bosch service centers as most shop have lousy testers