Hi,

 

Just become the owner of a Y-reg Fabia, and there are a few electrical oddities with it that I'm hoping someone will know the answers to:

 

1) Both headlights flicker quite badly (as do the instrument lights). I don't think it's the usual issue relating to the power steering pump, as it happens when stationary, but...

 

2) The PAS light comes on after about 10 mins of driving (fairly randomly). Steering doesn't seem to be affected, but I did notice it was heavy when parallel parking one time.

 

3) The electric windows are a bit iffy, but I think this may be the switches

 

4) The courtesy light doesn't go out automatically

 

5) I tried to connect with VCDS-Lite, but didn't get any response from any ECU. I've used the cable and software recently on an A3, so I'm fairly sure the setup is right.

 

I had a poke around last weekend. The battery has been upgraded to 60Ah, but I don't know how old it is.The alternator's charging at a constant 14V throughout the rev range, so it seems to be ok. The main earth between the battery and chassis is ok, and it's not got any problems starting.

 

I'm wondering if it's a bad earth (or relay) somewhere. Does anyone know where to start? I'm not frightened of getting the spanners out. I have owned several Alfas

 

Cheers,

Iain

Ooh, might be this. Will have a look at weekend. http://www.briskoda.net/forums/topic/336773-illumination-situation/?hl=%2Bflicker#entry4050411

I had those same wires BOTH snapped. 

Mine read 12v across battery with charged battery engine off and also with engine running on idle. Also the battery light never came on apart from a fraction of a second. It should come on when ignition on then go off when engine starts.

 

when I revved to 3000 revs the Volts went up to 14.2 and stayed at 14.1 when i put lights and heated rear window on.

 

After putting on ramps, undoing the plastic cover from below, and checking, both wires were snapped so had to re connect them (I used scotch blocks in the end as they were mega thin).

 

When I re tested, I noticed that the volts had gone to 14.3 at IDLE, also when i was in the car, the windows wound up and down faster, and I'd not noticed the PAS lag that I'd had before when occasionally pulling off the drive.

 

Definitely worth a check for BOTH wires.

 

Hope you crack it soon. 

Cheers for that. Had the quickest of looks today, and the wires and plug look in good condition.

 

Just trawling through the haynes manual to see if I can work out where they go though, so I can test for continuity....or does anyone know off the top of their heads.

 

Battery light behaves as it should. On with ignition, goes out when engine starts, doesn't come on once running.

 

Cheers,

 

Iain

The blue, exciter wire comes from the cabin, out of the control unit under where the relays go. 'Onboard electrical control unit' or something like that, they call it.

But I wouldn't bother looking at that one, as you've proved it is OK by the way the charge light behaves, I think.

 

The other wire, the DFM (field monitor/load sense) one turns from brown/red to lilac/green at the gearbox bracket connector, then goes on to pin 38 of the ECU connector, on your car (ASY engine code?), from what I can see.  From what I understand, that's the wire that tends to cause these 'after ten minutes running' warning lights when it's busted. It will also log fault codes in the ECU, if you can hook it up to VCDS.

Have a good look at the earth cables, even though they may look ok they could be earthing poor.

I replaced the battery-body earth cable on my VRS and it made a massive difference!

Been out to have another look today. Checked continuity in the loom from the alternator to the gearbox plug, all ok. Also checked the red (brown?)/green cable from the gearbox to the ECU - also fine.

 

So, I'm beginning to wonder if it's the alternator itself. The fact that it only starts after something has warmed up sounds a bit semi-conductorish to me, so maybe the diodes?

 

Thanks for all the info so far

 

Iain

 

PS Still no connection to any ECU, even with a new vagcom lead. :S

Edited 22 March, 201511 yr by iainfm

Further pondering on this before I can have another look. There's a bit of a squeak-squeak-squeak squeal coming from the aux belt area, so I'm wondering if the problem could be coming from the flywheel clutch on the alternator.

 

I might try to find a second one locally and fit it. Failing that, I could buy a new one.

 

I also need to check the charging voltage before and after the flickering starts...