Both low beams are out - please help
 

Info: 2002 Boxster S
Both low beams are out. High beams, running lights/fog lights work. Fuses look good. Cleaned the headlight switch with MAF. Purchased new headlight switch and installed it. Still no low beams.

How can I test the new switch to make sure it is good?

If that isn’t it, what is my next step? I also have the Durametric diagnostic tool. Can that help me?

Thanks for any assistance.

ecp

Did you check your fuses???

Sure did. No power going to them either. That’s why I went with replacing the switch

You could simply have burnt out bulbs. I read that you got a new switch, but nothing says that you checked your bulbs. Have you?

No power to the fuses???.....or no power to the lights???
Do all the other lights in the front work? (turn signals, parking lights?)

All the other lights work.

Right, both going out at the same time is unlikely. Additionally, no power leaving the 2 low beam fuses, so that means the bulbs are probably still good.

I did, they looked fine.

I would inspect the headlight wiring harness to your low beams. Due to aging, the insulation around the wires become brittle and flakes off exposing the wires. I coat mines recently with plasti dip (in can) using an arts/craft paint brush. You will need several coats.

The high beams and low beams use the same H7 bulbs. I would plug the high beam harness to your low beams to see if it works. If it works then you know it's not the bulbs. You already check the fuses but I would check again to make sure you are looking at the right diagram. Your car should come with a fuse diagram. If not, check the Bentley manual for the fuse diagram. Make sure it's the year for you since it varies.

"Looking" doesn't always count. Just recently I was schooled on how to actually TEST the fuse(s). They can look good... but looks can be deceiving.

Before you go cha$ing other gremlins... check the easy (free) stuff first.

Good luck.

Very unlikely indeed. But you'd be surprised how many people drive around not knowing one light has burned out until the second one goes and suddenly they have no lights.

In your case, since you've checked and found no power at the fuses, your problem seems to lie elsewhere. (Thanks, Capt. Obvious) My next guess would be your Low Beam Switch. That's what feeds fuses A9 and A10. Unless your car came equipped with Daytime Running lights. Then the DRL relay would also feed fuses A9 and A10.

Good luck.

I have replaced the switch and that didn’t work.

I tested them with a multimeter. They are good.

I tested one of the bulbs by swapping it out with a new one. Same result.

Have you checked the headlight relay ?

I am not getting a good ground on the A9,A10 fuses

You're not supposed to get a ground there, you're supposed to get 12v.

Did you also replace or look at the Hi/Low beam switch on the column? That's the one that feeds power to the fuses.

I'm dying to see what is the resolution. I'd be going crazy!!!

Could there be a headlight relay before the fuzes or after the fuzes before the lights.