Low beam headlights don't work

Sounds like a switch issue.

Check the bulbs could be blown low beam

Hi Ryan, check the fuse to the low beam, if your not getting power to the relay it will never work, the fact that you have 3 new relays they can't all be duff

low beam bulb quit

you don`t say if you have checked the fuses for the headlights.if the fuses are okay and you know that the low beam filaments are working.you may have to feed power and ground directly to the proper headlight prongs from the battery to make sure the bulbs are good.then it could be a relay for the low beams or a switch for the headlights.you don`t say if you have daytime running lights on this car as there is a module for this system that may be the problem for the now low beams.

if the fuses are good then you need to check for power and ground at the headlight plug that attaches to the headlight bulb if you have a good power and ground there and the connections are good then the bulbs are both no good.or if you can tell the bulbs are burnt out by looking at them then you don`t have to check powers and grounds.you also can directly feed power and ground to the bulb and check both the terminals for high beam and low beam as you cannot tell which is which by looking at the terminals

Both sides or just one? If both, The multi-function switch on the steering column is not working properly

Power flows from the battery to the main fuse. Then it flows to the control coil and contact side of the headlight relay. When you turn on the headlights, the headlight switch provides ground to the control coil in the headlight relay and that operates the contacts. The contacts allow power to flow to the right and left hand headlight fuses. Power flows to the headlights. The headlight switch is what provides ground to the high and low beams on the headlights.

To diagnose, remove the headlight relay. Using a voltmeter, check for battery voltage on terminals 3 & 4 in the socket with the key in the RUN position. Then turn on the low beams. Test for good ground on terminal 1 in the socket. If you're not getting ground, then you've got a problem with either a bad headlight combo switch or a bad ground. If you get good ground on terminal 1, reinstall the relay, turn on the low beams and test for power in the headlight sockets. If you get battery voltage, that confirms you've got good fuses and wiring up to that point. Next, check for good low beam ground on the red/green wire in the bulb socket. If you're not getting good ground, it's either a bad combo switch or bad ground from the combo switch. Then turn on the high beams and check for good ground on the red/yellow wire in the bulb sockets.

It wouldn't hurt to clean the ID ground on the left side of the instrument panel, but based on everything you've said so far, this sounds like a bad combo switch

https://s12.postimg.org/6o2zcv3hp/jetta_headlamps.jpg

Click on the link.
This is for 03 jetta gls
There are fuses for left and right low beams. Headlights on low beam, use a test light, see if voltage on fuse circuit? If no voltage that will lead us back to dimmer switch or problem with wiring circuit from dimmer switch.

I have e-mailed you 2 .pdf files, one is the complete headlamp diagram, and the other is the relay locations. Please advise if you need further assistance.

Toyota Ed