# MK2 Jetta high beams are working, headlights arent



## Si Trav (Oct 26, 2008)

All the lights on the front end of the car work except for the head lights. 

Fuses are good bulbs are good(hi beams work) 

what could it be?


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## cuppie (May 4, 2005)

Just because the hi beams work, does **not** automatically mean that the bulbs are OK. Hi and Lo are separate filaments in the bulb.

So, check the bulbs. Remove them, and actually take a look at them. Lo-beam filaments broken? If=yes, replace bulbs.
If=no, still replace a bulb (worst case, you have a spare for another time, when you do blow a bulb.)

New bulb, still not working? Check power to lamp. Check low-beam fuses (1 and 2.) Check power to F1 and F2 - should be ~battery voltage, when low-beams are switched on.
If there's no power at the fuses, it's most likely a failed turn/dimmer switch.

But, simply having burned-out bulbs is still more likely.


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## Si Trav (Oct 26, 2008)

cuppie said:


> Just because the hi beams work, does **not** automatically mean that the bulbs are OK. Hi and Lo are separate filaments in the bulb.
> 
> So, check the bulbs. Remove them, and actually take a look at them. Lo-beam filaments broken? If=yes, replace bulbs.
> If=no, still replace a bulb (worst case, you have a spare for another time, when you do blow a bulb.)
> ...


thanks so much i am gonna try it out tomorrow


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## Si Trav (Oct 26, 2008)

Si Trav said:


> thanks so much i am gonna try it out tomorrow


swapped bulbs and nothing.


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## cuppie (May 4, 2005)

Okay. Aforementioned fuses verified as OK (read: they've been swapped with new fuses, and/or voltage has been checked at the fuses with the lo-beams on)?


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## aldin270 (May 13, 2011)

I hate to resurrect a thread from the dead, but I'm having a similar problem. I was driving tonight and my low-beams suddenly stopped working, but when i turn my high-beams on both my low beams and high beams are working. I drive a 89 GLI that has the GTI front end with the Oo oO configuration. I already checked all the fuses and i know its getting power because when the high beams are turned on the low beams are working. I replaced the bulbs still not working. All of the interior lights work, the gauge cluster is working, the marker lamps, tail lights, basically everything but my low beams when my high beams are off, anyone have any idea as to what it could be? Another thing I have noticed is that when i do turn the high beams on, normally it would click to keep them on, but now its not doing it, I think its either the dimmer part where you turn the lights on or the actual high beam switch but i am not certain. Any help would be appreciated.


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## cuppie (May 4, 2005)

Two things:
1: That the dimmer switch (which is part of the turn signal switch) no longer goes 'click' when you pull it back all the way means that it's mechanically broken, and needs new. Replace that before you continue diagnosing the lights.
2: You do realize that the outer lights are Hi/Lo beam lamps, right? Dual-filament lamps, each filament fed by its own wire (and, its own fuse.) Just because the _high_ beam in that lamp works, means nothing about functionality of the _low_ beam.  


One other thing:
Let's assume that the dimmer switch has actually been broken for a while. It's a possibility - how often do you actually use high beams?
There's always the possibility that the electrical part of the switch is fine, but the mechanical latch failed. If that happened (and, it does happen), the reason that the lights work (on Hi only) when you pull the switch is because there's no X-contact (key-on) power available to the switch. And, that's usually due to a failed ignition switch.

So, one other thing to look at and consider:
Pop the headlight switch out. Grab thy voltmeter, and connect it to the X terminal there, and to ground. Turn key on (leave lights off.)
If power OK, move on to next stop. If power not OK, replace ignition switch.
Power OK on previous check? Turn headlights on. If power suddenly not OK, ignition switch has failed, and (again) needs new.


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## aldin270 (May 13, 2011)

alright, is the turn signal switch related to the low beams at all or not? I'm leaning more towards the actual switch that i turn my lights on with, or do you think that is out of the question ?


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## cuppie (May 4, 2005)

Yes, it is, because it also houses the dimmer (Hi/Lo) switch.

But, like I said, before you go and replace the headlight switch, see if there's power available to it (at the X terminal) when the key is on.
If there is, then see if there's power coming out of it (56 terminal) when the headlights are switched on.


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## blk183 (Dec 18, 2015)

Sorry to resurrect a very dead thread but I'm having a similar issue. There's power at my X-terminal but none coming out of the 56 terminal. This mean the headlight switch is buggered or the ignition?


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## cuppie (May 4, 2005)

You need a headlight switch. 
X is power from the ignition switch, 56 is the output to the headlights. 

Since you have power at X (with the key on), then the ignition switch is OK. But, no power out at 56 (with the headlights switched on, of course), while there is power at X, means that the headlight switch failed.


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## blk183 (Dec 18, 2015)

Thanks mate! New one on order


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## evilqueen (Jan 4, 2017)

bringing this back
i took out old foglight wiring would this cause any problems with headlights


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## cuppie (May 4, 2005)

evilqueen said:


> bringing this back
> i took out old foglight wiring would this cause any problems with headlights


 Well, that depends on how the (presumably aftermarket?) fogs were wired. 

I'm guessing that "headlights worked before, but now don't work"? If that's the case, check your work, see if you broke some of the factory headlight wiring. 
Consult wiring diagram in Bentley for current flow.


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