Classic Retrofit and Old Headlight Fuse/Relay Connections

[OsoMoore]

I'm installing a Classic Retrofit fuse box from our host. My car has a non-kit headlight relay setup installed, and I don't know how to integrate it with the new fuse box's fuse/relay system.

In my current system, wires were run straight from the ignition-switched power (top of fuse #7 from left). Those wires ran through two fuses and to two relays. One for high beams, one for low beams.
The relay wiring is shown below.


The schematic for this section is shown below.
L1 - Left headlight
L2 - Right headlight
S5 through S8 are fuses 5 through 8, apparently numbered from the right-hand side of the stock fuse box.


Based on the picture below from the fuse panel seller's website, I should connect the white wire into top of the pair labeled 1 & 2, immediately left of the relays.
I should wire the solo solid yellow wire into the top of the pair labeled 3 & 4 immediately right of the relays (3 & 4 are not bussed together on my panel, so I should add a jumper).
Then blue goes to bottom of 1, blue/white goes to bottom 2, green/yellow goes to bottom 3, and other yellow (from pair) goes to bottom 4.
However I have no idea where the red wires are supposed to go.


That's my best guess as to which fuses to wire to in the new fuse panel. If anyone knows for sure, I would appreciate your input!

Edit: After more research and analysis, it looks like I don't need the red wires at all. Just hooking up the other wires as I indicated above. The manual for classic retrofit says power is run internally through the block.

[OsoMoore]

Update: I hooked up the wires using what looked like the old/correct wiring.
I found the following issue:
Low and High Beam Fuses In: Neither highs nor lows work.
High Beam Fuses Only: Neither highs nor lows work.
Low Beam Fuses Only: Low beams work, when I try to switch to high the lights flicker and a relay buzzes nonstop.

[fred cook]

I think I see your problem.You can't run the same power wire (from switch) to feed both the high and low relays. The yellow wire from the switch should only go to the low beam relay and the white wire from the switch should only feed the high beam relay. Everything else looks to be ok. It would help to know what year your car happens to be!

[timmy2]

Top fuse wiring looks ok. But I’d move the white wire in the top of fuse 8 over one to the right to go in fuse 7.

Can’t see what is coming out the bottom of each fuse 5-8 going to the lights though?
What are the red wires that look like they are coming out the bottom of fuse 8?

Should be wired with the colors exactly the same as in the schematic.
Only one wire out of each of 5 and 6 for the low beams, and one each to the high beams (plus the hi beam dash indication wire bottom of 8) for 7 and 8.

Porsche schematics count the fuses from the headlight end to the dash. Ignore the markings on the cover or on the fuse panel…

[timmy2]

Here is a photo of mine from when I replaced my dash harness a month ago and installed the same fuse panel.
Fuse 5 and 6 are low beam. 7 and 8 are high beam.
Wish I had a better photo, but carpet is back in now.
I chose to use fuse 5 instead of 6 for the low beams input on top.

[timmy2]

Looking at your photo more. What color wire is coming out of the bottom of fuse 6 that has the yellow wire the the terminal on top? If it is white/blue it should go to fuse 8 two to the left and there should be a yellow/green wire at the bottom of fuse 6.

[OsoMoore]

Hey folks, for thanks for the input. Here are some pictures of my box (the picture earlier was on the installer's website.) Full description of my setup is below the images.




The car is a 1979 911 SC.
This is the Classic Retrofit fuse panel, so there is a built-in relay kit. The installation instructions say to return things to stock, and the panel's internals will handle the relay work. I don't know for sure what is stock, but I'm pretty sure I've gotten there now.

My connections are:
High Beam feed wire (white) is spliced into blue. That blue wire goes to the top of the high beam pair (which are bussed internally) on the left of the relays. That's positions 7 & 8. On the bottom of 7, I have the blue wire with the white stripe. On the bottom of 8, I have the blue wire and the white wire with a blue stripe.

Low Beam feed wire (yellow) leads to the top of 6. There's no internal bus, so I have the copper jumper between 5 & 6. On the bottom the green/yellow wire is connected to 6, and the yellow wire is connected to 5.

Since my earlier testing, I added an improved ground wire to the fuse panel board. The full behavior can be seen in this video. Test starts at 45 seconds: https://youtu.be/E0EcOfFAQz8

What the video shows is when I turn on low beams, they come on just fine. When I flip on high beams, they come on but a relay buzzes nonstop.
If I pull out just the low beam fuses, I get no low beams and also no high beams.
If I pull out just the high beam fuses, I have low beams, and buzzing when I try to turn on high beams (but no actual high beams). When the relay is buzzing here, the low beams are dimmed.

[OsoMoore]

Originally Posted by fred cook

I think I see your problem.You can't run the same power wire (from switch) to feed both the high and low relays. The yellow wire from the switch should only go to the low beam relay and the white wire from the switch should only feed the high beam relay. Everything else looks to be ok. It would help to know what year your car happens to be!

I'm currently running the feed wires as you describe. Note that the white wire is spliced to blue, so you see the blue wire connecting on top. Car is 1979 911 SC.

Tim's questions:
I can move the white wire from 8 over to 7. Theoretically they should be the same due to the internal bus. But I'm happy to try anything.
Do you have the internal bus for 5 & 6? My board isn't marked with one, which is why I put in the copper jumper.
As noted above, I have the colors at the bottom of the panel looking correct.

Update: I might be having the issue because I only have mounting screws at the ends of the fuse panel, and not in the middle spots in the panel. It might be relying on a middle screw for ground for the relays. I haven't had those middle screws in years. Does anyone know what spec they are offhand? I can always pull out one of the end ones and take it to the store to match, assuming they are identical.

[pete3799]

That may be your problem....missing ground on the relays.

[timmy2]

Did you confirm 5/6 are not connected up top with a meter?
Mine works fine using 5 for low and 7 for high as the only relay inputs.
Maybe I read something in the instructions that said go to 5?

[OsoMoore]

Originally Posted by pete3799

That may be your problem....missing ground on the relays.

Ding ding ding! Classic Retrofit confirmed this was the issue. I added a screw to the middle spot with a good ground and now there is no more buzzing. But wait, there's more!
Now, once I turn the headlights on, I can never turn them back off. I have to disconnect the battery. Turning switch off, ignition off, and removing the key doesn't turn them off.

Originally Posted by timmy2

Did you confirm 5/6 are not connected up top with a meter?
Mine works fine using 5 for low and 7 for high as the only relay inputs.
Maybe I read something in the instructions that said go to 5?

I removed the gang/bus I had put in between 5 and 6, and verified they did not "naturally" have a connection built in. Then I poked around a little more... and found something very strange.

1) Disconnected the low beam feed wire (yellow) that was at the top of 5&6. Removed the bus I had put in between 5 and 6. Verified 5 did not connect to 6 without the bus.
2) On a whim, checked if 5 was connected elsewhere. Found 5 was connected to 2, 3, and 4 (according to my continuity test multimeter).
3) Pulled all the fuses for 2, 3, 4, 5, and 6.
4) Found 5 was now only connected to 3.

Again, note that the yellow feed was removed from 5/6. Yet without any fuses, 5 was connecting to 3. I've got a video I took that I can post in a bit. Very odd!

EDIT: Videos of the weirdness:
https://youtu.be/4XvDYqA6zBc
https://youtu.be/4eNMIPBQAdM

[timmy2]

Normal… You are measuring through the bulbs and back unless all wires and fuses are removed.

[OsoMoore]

Hmm, I was wondering why five would connect to three when five had no fuse and no wire from the headlights either (video 2). But maybe I am misunderstanding something about it.

[timmy2]

If you are testing the fuse panel itself, remove all wires and fuses.
Otherwise you are measuring through all devices connected to it that have possible paths back.
Light bulbs being a prime example. Goes through headlight lamp to ground and back from ground through the tail lights or front running lights. Both front and rear running lights and license plate lights come off of fuse positions 2,3,4. Fronts are fused, rears are not.

[OsoMoore]

Originally Posted by timmy2

If you are testing the fuse panel itself, remove all wires and fuses.
Otherwise you are measuring through all devices connected to it that have possible paths back.
Light bulbs being a prime example. Goes through headlight lamp to ground and back from ground through the tail lights or front running lights. Both front and rear running lights and license plate lights come off of fuse positions 2,3,4. Fronts are fused, rears are not.

Ok, I may have to do that next. The headlights "locking" on is really weird. It seems like maybe their power to flip the relays is also running to the lights themselves, or something like that.

[7783911]

On their website are PDF instruction which include a separate page for the relays, I removed my Jwest relays and used their on board relays following those instructions and had no issues

I ll post a picture later today

[OsoMoore]

Originally Posted by 7783911

On their website are PDF instruction which include a separate page for the relays, I removed my Jwest relays and used their on board relays following those instructions and had no issues

I ll post a picture later today

That would be appreciated. I tried to match stock with my wiring, but seeing as I never owned the car with a stock or official relay kit, I'm not 100% sure.

[timmy2]

Pull the 4 fuses for the hi/low lights.
Do relays still pick up in both hi or low beam selection?
If yes, inputs are correct.
If not, then the blue and/or white wire(s) need to swap positions from bottom to top. (Either one or both depending on what happens for hi/low selection and relay action.

[OsoMoore]

Originally Posted by timmy2

Pull the 4 fuses for the hi/low lights.
Do relays still pick up in both hi or low beam selection?
If yes, inputs are correct.
If not, then the blue and/or white wire(s) need to swap positions from bottom to top. (Either one or both depending on what happens for hi/low selection and relay action.

Sounds good Timmy. I'll pull those fuses. To determine if the relays are holding... I guess I can flip lights on, then off, and listen for a relay click when I turn them off. And listen for a click while disconnecting the battery.
Sounds like a good task for having a helper. Fortunately my wire loves riding in the car.

[Jonny H]

Please don’t link F5 & F6. The yellow wire should be in 6 (next to the relay). 5 bypasses the relay as per European models that use a electronic dim/dip circuit that cannot be switched with a relay.