Hi all,

I just took my VRS for its MOT (and it passed - yay!). It hadn't been driven for about 6 weeks but I'd had it on a trickle charger a couple of times and it seemed fine driving the 4 or 5 miles to the garage.

However when there, the tester came out and asked me "Do you know your car is not charging the battery properly? The battery light keeps coming on"

Now I'd never noticed this before or even on the drive down there. Anyway, the car passed the MOT fine but they had to connect a battery booster because apparently it was affecting the emissions results?

When I got back in to go home there were no warning lights on. HOWEVER, before I drove off I rev'd it a couple of times to about 2,000 rpm and this made both the ABS and ASR lights come on together for about a second each time.

Driving off it didn't happen again and the car drove normally on the way home except for a split second when coming up to a roundabout the battery light flashed on.

I need to get it serviced soon anyway but thought I'd post here to see if anyone had any ideas what the problem is? Could it just be it's unhappy after being sat since the start of October?

battery may be low on charge give it a decent run and see if the problem occurs again

replacement battery not too bad - bosch S4 around £50 from ecp

If I recall correctly those lights came on when I had a boost leak.

It'd be good to get your car scanned for fault codes, see what comes up.

I ha this before my car died, changed the alternator didn't fix and battery tested fine... Looking for bad earth now... Plant your foot, do you get boost or nothing?

Thanks for your help guys.

The car drives the same as always. I suspect there may be some kind of boost leak as at low revs it feels or sounds like it's overboosting then dieing. This is very noticeable if I drive off before the secondary air pump has finished, but there is still a slight hesitation at other times. When it happens you get the whistling sound of a turbo spinning up but no acceleration, then a couple of seconds later a small loss of power. Idle rpm is stable at about 800.

A few months ago I got a 17705 error code and engine light that turned off after a week or so. I'll try plugging my laptop in again and see but there's no engine management light on the dash at the moment.

I've been thinking of taking it to VAGTech who are fairly close to me for a check over and 80k service. Their website looks good and I think I'll get a better service there than at a Skoda dealer.

My money is on bad earth, same problem as I suspect I have...

Yeah, it's weird on mine as it has never happened before, and in fact like I said above it didn't happen even driving it down there today, it only started while they were testing it.

Just remembered something I left out of my original post...

The garage left the engine running after they finished the MOT in case it wouldn't start again. When I got back in and closed the door I think I saw the ABS/ASR lights come on once or twice then as well just when it was idling. I pressed the ASR button to see if the light stayed on but it didn't seem to do anything.

Thinking about it now, I wonder if maybe the battery was just a bit low and then when they started the test they left the ignition and headlights on etc and this drained the battery enough to start causing these problems? The car turned over and started fine to drive it down there so the battery can't have been that bad.

Had a new mechanic out today and confirmed a corroded earth cable... Said it was very badly burnt.

Run the engine on yours, is the fuse box on top hot??

Also stick a multimeter on the battery and post the results...

Where was the earth exactly?

Follow the black wire from the battery and you'll find it!

Just an update... the mechanic who fitted my new thermostat today also tested the voltage for me and the battery was only outputting 12.6 volts with the engine running and 12.0 with it off - which he told me means that the alternator is not giving it any power. He's coming back to replace it on sunday.

Strangely there were no warning lights on the dash so I went for a drive to collect my shopping only for the battery light to come on, the airbag light to come on and the dash needles to die so the revs, speed, temp, and fuel all read 0. This happened at 60mph on the A1! I just about controlled my panic, turned round at the next junction and made it home!

Edited 2 December, 201114 yr by OU51