flickering lights

[edd 0]

heys folks

 

Got an interesting problem on the C when changing gear with the full beam on the lights flicker and momentarily lose their brightness (or should i say dullness, no uprated loom yet!!), prob flicker for about two seconds. If i hold the car on a hill in first with clutch on its biting point they will do it for a longer period of time. i.e. just as the engine is put under load. A friend mentioned it may have been an earthing problem as the engine shifts on its mounts slgihtly under acceleration. I have since fitted a new direct earth from engine block to battery negative, this seems to have helped slightly but its certainly not been eliminated. anyone got any ideas??? voltmeter over battery is reading 13.9 volts and pretty stable.

[h100vw 0]

It might be an alternator output issue. As you dip the clutch the engine and alternator slow down. The output of the A drops off slightly and your dim lights get dimmer??

 

Have a look at the lead from the battery to the starter. The alternator power goes there too, maybe it is corroded or needs tightening?

 

All the above may of course be cobblers :shock:

 

Gavin

 

read below

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[edd 0]

cheers will have a look, if all seems fine connection wise is it likely to be a case of a new alternator then, like i said its pushing out a consistent 13.8V with engine running and stereos and fan on and stuff?

[h100vw 0]

I can get an alternator rebuilt in Warrington for less than £30. New bearings etc. I'd look in to that before buying a recon from GSF or somewhere.

 

In fact I had mine bench tested before and just bought a brush pack. for a tenner.

 

Gavin

[dr_mat 0]

If the voltage across the battery doesn't drop, even when the lights are flickering, then the problem is not likely to be the alternator, I'd say.

[edd 0]

messin around tonight and now find that if i hold the car on slight incline in reverse and move very slowly backwards with full beam on the lights will dim/flicker as before but not as the clutch is released to its biting point but as it pressed away from it. i.e car is allowed to roll forward. Shed anymore light?? Think maybe it is alternator though as am finding if i keep in high gear at slow speeds (low revs) so the c is close to stalling light are definatley at their dimmest. The c is also idling at just a touch over 1000 revs, which it has done since ive had it, its 1.8 16v. is this a little high!! cheers

[Riki 0]

16 v,s are supposed to idle at 1000 rpm.

[dr_mat 0]

It's not a big V6.. VRs tend to idle at a comfortable 650rpm.. :)

 

The final test. Stick the handbrake on, put it in gear, lift the clutch gently. Do the lights get dim as the revs drop?

Do the lights get brighter if you rev the engine?

If no to both of these I seriously doubt it's the alternator!!

[Borat 0]

speaking of lights, when i rev my engine the lights go brighter. However, the connection on the back of the head lights are not the george as i have to keep pressing them back on. also when i use the electric windows the interior lights dim. :?

[edd 0]

right then lads had another bit of a peek in the dark tonight cos im gettin a little frustrated, which lights are maent to be on with the full beam as it doesnt really make it clear in the manual. With my full beam on the foglight units are on. Not bright enough to be on as foglights but they are on and i think it is these imparticular that are flickering. Are these meant to be on in this situation. As i have had problems with the fuses blowing in the fogs and now think that they may have been wired by the past owner to come on with the full beam as there are a few odd wires under the hood. Problem is there is still remains of old alarm so its hard to tell whats what! Can anyone shed any light. I think its almost defo time for an auto electrician!! ouch ...££

[Borat 0]

ed mate

when i am on full beam the fogs are not on. Mine is a 2.0 16v and as far as i am aware this is correct. The fogs are activated seperately and should not come on when you activate full beam. The floatng/odd :? wires are a bit strange tho mate

hope this helps

[h100vw 0]

edd, the fogs are in the bumper and the lights you seem to be talking about are the spotlights. The ones that are in the headlights. What should occur is, the outer headlights come on when you turn on the lights.

 

When you flick on the main beam at the stalk, the outer lights go to main beam and the spots come on then.

 

Having read your post again, it does sound that the PO has messed about with it, due to the poor std lights.

 

I'd get it put back to std and then think about an uprated headlight loom, that will allow you to get the best from your lights.

 

Gavin

[edd 0]

cheers guys yep it was my fog lights that were coming on with the main beam, think they have defo been messed with to compensate for s**t standard lights. Interestingly my left spoltlight bulb (I think?? if i undesrtood gavins post properly!!) blew on the way home tonight so on full beam my right light is emitting nothing at all but i have a light on with them dipped. But this way i have no flickering whatsoever!!!!! (wehey) so at least i know that its something to do with the circuit on the right side now.

[h100vw 0]

The flickering could have been a broken filament, that was making and breaking due to vibration. Now it bust completely, no more flickering.

 

 

 

Gavin

[edd 0]

nah this driving me mad now wasnt the bulb it was the fuse, taken all the lights apart etc checked the connections and bulbs. all light circuits in engine bay look okay, but i am now almost certain the fogs have been rewired to work with main beam as well as their own switch. have suspicion they are fed from the right main beam switch though! maybe thats what is causing the fuxe to burn now and the flickering before. Im gonna have to get the fuse box out though to see if there is anything weird goin on behind there. Have got full set off electronic circuit diagrams from http://www.volkswagen.msk.ru worth a look guys its in russian but has eng pdf files i suggest search on google to get the most legible page

[edd 0]

right lads sussed it finally!! My air intake unit behind the front right light is quite loose (not sure if it meant to be!!) anyway its movement over time had worn right through the insulation on three of the right lighting loom wires thereby causing them to short. cut them and reconected them with cable connectors and now all sorted no flickering fogs main beam spots everything sweet!! so close to callin auto electrician!! coulda been a 50 pound job rather than five. Anyway cheers for the suggestions. If anyone else has a similar problem maybe its worth a look!!

[dubster82 0]

yeah, i nearly got that too, i had to tape my loom up with insulation tape to make sure that didnt happen!