Passenger side headlight doesn't work(bulbs good) and NO HIGHBEAMS!

[74vert]

The passenger side headlight worked when i first got the car but once i removed the housing to check the bulb for highbeams it no longer works

H4 setup on car now

1974 911

Low beams work fine but highbeams never worked and the passenger side no longer works now

Can someone provide me with a wiring diagram and pointers?
I need to know how to find a signal/power wire to check if my switch on steering column works for highbeams

I want to just completely rewire the headlights, maybe make one of those H4 wiring harness/relay kits to run it directly off the battery like this one on ebay does

Headlight Tune Up Kit 9003 H4 14 AWG Relay Harness with Nokya Hi Wattage Bulbs | eBay

[DRACO A5OG]

Check the ground for the high beam, it may be loose or not connected.

Pull the driver side so you know what to look for.

After that, fuse, make sure it is seated and the wire is connected fully.

[porwolf]

There are so many connections along the way from the battery to the light bulbs. Any one or several could be poor and cause the problem. The first order should be to install a relay kit. Then the current runs directly from the battery to the headlights. But your light switch and your directional switch could be the problem. You need to go step by step to check voltages along the path from the battery to the light bulbs. don't ignore the current return path through the ground contacts, again, all the way from the light bulbs to the battery. and since you seem to be using 90/100W light bulbs one or more of your connections could have been burned/oxidized so much that not much current can run through anymore.

[74vert]

What plug on the firewall should i clean? What wires under the dash/switch should be hot? Colors?
Schematics anything?

Thanks guys. Im about to build a relay kit i suppose, 14 gauge wire sound good? How many amp fuses? And what kind of relays should i use?

[porwolf]

Originally Posted by 74vert

What plug on the firewall should i clean? What wires under the dash/switch should be hot? Colors?
Schematics anything?

Thanks guys. Im about to build a relay kit i suppose, 14 gauge wire sound good? How many amp fuses? And what kind of relays should i use?

For electrical schematics I would use mu Bentley manual. But our host also has some available here:

Pelican Parts - Porsche 914 Electrical Diagrams

14 gauge wire sounds good if it only carries current for one light bulb filament (high or low beam). I made my own relay kit with 4 relays, 1 for each filament. Just to be sure I used four 12 gauge wires from the battery to the four relay switches. I may have overdone it but better over design than underdesign. The relays by themselves are cheap, about $5.- each. I used four 8 Amp fuses in my four wires from the battery to the relays. Actually I saw that some relays come with built-in ATO fuse holders:

[HarryD]

Do you have a test light or meter and know how to use it?

Sounds like two problems: one low beam out and no high beams. You need go check each separately.

For the low beam, check your fuses, you have one for each lamp. Since one is working, the problem is between the fuse box and the lamp. I would guess a bad fuse or loose wire at the lamp.

Since both hi beams are out, it may be your high beam switch. You will need to verify power at your fuse block to determine where to look next.

[timmy2]

Pelican Parts - Porsche 911 Parts Listings & Diagrams
The '78 drawing will be close,
The '73 is difficult to follow in comparison.

[HarryD]

I would suggest 12 gauge wire and 20 amp fuses. One relay for high beams and one for low beams.

Here is some good discussion on relay installation: Headlight Relays Redux

[74vert]

what are the two relays above the fuse panel near the battery?
are there supposed to be more than two?
my fuses are all good/there

what color are the wires for the headlights?

[timmy2]

Why not post a picture of what you are talking about.
Relays on your car?

[Algernon]

Relays are cheap and using 4 means lower current all round, so easier to wire up.

[porwolf]

Algermon, I know there are those relays with integral ATO fuses but I don't know a good source. Where did you get yours?

[porwolf]

Originally Posted by 74vert

what are the two relays above the fuse panel near the battery?
are there supposed to be more than two?
my fuses are all good/there

what color are the wires for the headlights?

Why don't you show a picture of your setup.

[Algernon]

Originally Posted by porwolf

Algermon, I know there are those relays with integral ATO fuses but I don't know a good source. Where did you get yours?

From our host 911-615-103-01-M504,
$7.25 each.
tabs are metal and I folded them through a right angle to fit the bracket I made. I repositioned the existing wires which were long enough to reach new contacts without any joins!!

[porwolf]

Originally Posted by Algernon

From our host 911-615-103-01-M504,
$7.25 each.
tabs are metal and I folded them through a right angle to fit the bracket I made. I repositioned the wires which were long enough to reach new contacts without any joins!!

That is the best headlight relay solution that I have seen. Congratulations Algermon!