1986 944 Relay Help!

[Jacquiles]

Ok so now that i’m getting close to being able to drive my 944, i thought i may as well attend to the smaller interior issues and electrical issues while i wait for parts to arrive. Here are a few photos showing the relays in their current position.

IMG_1722.jpeg (2.97 MiB) Viewed 1252 times

IMG_1721.jpeg (3.79 MiB) Viewed 1252 times

IMG_1720.jpeg (4.01 MiB) Viewed 1252 times

I do realize i am missing my g10 fan relay, i have a used one i’m getting soon. But i was curious if anyone who has a 944 just like mine could let me reference their correct relay setup so i can make absolutely certain i have the right relays in the right places so that when/if i need to diagnose other electrical issues i’m not chasing my tail. Right now the problem i was concerned with was my sunroof not working. It appears the motor for my sunroof is in the rear driver side quarter panel and has two brown relays mounted to it. My sunroof currently does not operate at all. I verified the fuse is good so far and that there is power at at least these two
terminals at relay spot g21.

IMG_1719.jpeg (213.8 KiB) Viewed 1252 times

Also note that whenever i place that silver relay in my hand into spot g21, the fuse for the sunroof circuit, number 8, pops. Also my pop up and down headlights do not, well, pop up and down. Currently the headlights are not installed, but the motor still does not operate. Before i go checking power at different wires for all these problems i want to verify my relays and that they are in the right spots. That is the main reason for this post. As to the actual reason why these different accessories don’t work, im confident i can figure out, although any tips are greatly appreciated, but for the most part i just need relay info.

[Bergerac]

Download the PET from Porsche , there's a section which tells you which relay part number goes in each location

[Jacquiles]

Download the PET from Porsche , there's a section which tells you which relay part number goes in each location

I checked this out and it was pretty helpful although it wasn’t a total match to how the relays are in my car. mine has a spot for g21 relay but they don’t even list that one on the PET. In the PET it says it’s for an 88s2944 so idk if that’s the difference

[usury]

Here's my fuse box (central electrics) from my 1987 944na. The flasher relay is aftermarket (with an adjuster knob for LED turn signal rate control, adjacent to the DME relay). Otherwise, I believe everything else in there is stock.

PXL_20230807_170516655.jpg (158.33 KiB) Viewed 1211 times

PXL_20230807_170521885.jpg (145.5 KiB) Viewed 1211 times

PXL_20230807_170527472.jpg (352.04 KiB) Viewed 1211 times

PXL_20230807_170531368.jpg (138.41 KiB) Viewed 1211 times

[dr bob]

The 928 615 124 01 relay is for ABS. Superseded by 03 if that helps. It's listed for 86.5-on 928 cars, pretty much all the 928's available with ABS.

[Tom]

Have to say I'm a bit stumped. Spent quite a bit of time looking up fuse boxes and sunroof relays and have concluded the factory info from the era seems inconsistent with reality (as are some of the fuse box cover legends). Everything I can find from Porsche says that the sunroof relay is G18 on 1986 cars. On my 1986 944 Turbo, the sunroof relays is indeed in G18, and the spot for G21 is blank with no socket. Are you 100% sure your car is an '86? Run the VIN against one of the online VIN decoders if there's any doubt. I don't think there is any scenario where that relay (928 615 124 01) belongs in G21 -- unless it's a DIY project of some kind. I also can't quite figure out why you have an add-in relay socket in G21, although I know Porsche does use those, so perhaps that was there way of making a universal fuse box work. (Maybe look up under the dash to see if there are any signs it was a DIY add-on for something added after the fact).

I'd would be inclined to get a sunroof relay (944 615 117 02) and put it in your G21 location. One could easily imagine the wrong relay shorting a circuit and popping a fuse like you are seeing, so I'd say there is a reasonable chance the right sunroof relay will fix the issue.

[Jacquiles]

Have to say I'm a bit stumped. Spent quite a bit of time looking up fuse boxes and sunroof relays and have concluded the factory info from the era seems inconsistent with reality (as are some of the fuse box cover legends). Everything I can find from Porsche says that the sunroof relay is G18 on 1986 cars. On my 1986 944 Turbo, the sunroof relays is indeed in G18, and the spot for G21 is blank with no socket. Are you 100% sure your car is an '86? Run the VIN against one of the online VIN decoders if there's any doubt. I don't think there is any scenario where that relay (928 615 124 01) belongs in G21 -- unless it's a DIY project of some kind. I also can't quite figure out why you have an add-in relay socket in G21, although I know Porsche does use those, so perhaps that was there way of making a universal fuse box work. (Maybe look up under the dash to see if there are any signs it was a DIY add-on for something added after the fact).

I'd would be inclined to get a sunroof relay (944 615 117 02) and put it in your G21 location. One could easily imagine the wrong relay shorting a circuit and popping a fuse like you are seeing, so I'd say there is a reasonable chance the right sunroof relay will fix the issue.

Here’s my vin: WP0AA0943GN453856

That is quite strange. So i actually found that my sunroof relay is in the g16 spot which is not for the sunroof so when i moved it to the g21 spot to try it the sunroof still doesn’t work. i ordered a complete used set of relays for this car for 95 bucks so we will try that and then i’ll have all the right relays in the right spots and be able to start identifying and isolating the problem. In the image of the relay box it has a relay in the g21 spot aswell so maybe Porsche just has a discrepancy on relay layout??

[Tom]

Have to say I'm a bit stumped. Spent quite a bit of time looking up fuse boxes and sunroof relays and have concluded the factory info from the era seems inconsistent with reality (as are some of the fuse box cover legends). Everything I can find from Porsche says that the sunroof relay is G18 on 1986 cars. On my 1986 944 Turbo, the sunroof relays is indeed in G18, and the spot for G21 is blank with no socket. Are you 100% sure your car is an '86? Run the VIN against one of the online VIN decoders if there's any doubt. I don't think there is any scenario where that relay (928 615 124 01) belongs in G21 -- unless it's a DIY project of some kind. I also can't quite figure out why you have an add-in relay socket in G21, although I know Porsche does use those, so perhaps that was there way of making a universal fuse box work. (Maybe look up under the dash to see if there are any signs it was a DIY add-on for something added after the fact).

I'd would be inclined to get a sunroof relay (944 615 117 02) and put it in your G21 location. One could easily imagine the wrong relay shorting a circuit and popping a fuse like you are seeing, so I'd say there is a reasonable chance the right sunroof relay will fix the issue.

Here’s my vin: WP0AA0943GN453856

That is quite strange. So i actually found that my sunroof relay is in the g16 spot which is not for the sunroof so when i moved it to the g21 spot to try it the sunroof still doesn’t work. i ordered a complete used set of relays for this car for 95 bucks so we will try that and then i’ll have all the right relays in the right spots and be able to start identifying and isolating the problem. In the image of the relay box it has a relay in the g21 spot aswell so maybe Porsche just has a discrepancy on relay layout??

G16 for the buzzer/gong that goes off when you have the key in the ignition and the door open. It's the relay with the little speaker-grille opening on the top for sound. I don't see one in your pictures though. I'm assuming your car does not have a warning buzzer right now? Someone must have gotten mixed up and/or started plugging in random relays for some reason. Keep in mind there are lots of things beyond that relay that can prevent the sunroof from working. When you plugged the sunroof relay into G21, did the fuse 8 blow like it did with the ABS relay. If not, that would at least confirm the ABS relay was the cause of the fuse-burning short. Do you know about Clarks? If not, see here for sunroof diagnostics:

http://www.clarks-garage.com/shop-manual/body-03.htm

Your VIN is an '86 model and there is most certainly a disconnect between the factory manual/schematic and your fuse box. If it was an isolated incident, I'd wonder if someone swapped a latter fuse box into your car, but others have reported similar discrepancies. I think you have to work on the belief that g21 is the sunroof relay. If a new relay doesn't fix it, I'd go through the other diagnostics and, to just to confirm, I'd probably ohm out the G21 socket to the rest of the sunroof circuit just to make sure.

[Jacquiles]

Have to say I'm a bit stumped. Spent quite a bit of time looking up fuse boxes and sunroof relays and have concluded the factory info from the era seems inconsistent with reality (as are some of the fuse box cover legends). Everything I can find from Porsche says that the sunroof relay is G18 on 1986 cars. On my 1986 944 Turbo, the sunroof relays is indeed in G18, and the spot for G21 is blank with no socket. Are you 100% sure your car is an '86? Run the VIN against one of the online VIN decoders if there's any doubt. I don't think there is any scenario where that relay (928 615 124 01) belongs in G21 -- unless it's a DIY project of some kind. I also can't quite figure out why you have an add-in relay socket in G21, although I know Porsche does use those, so perhaps that was there way of making a universal fuse box work. (Maybe look up under the dash to see if there are any signs it was a DIY add-on for something added after the fact).

I'd would be inclined to get a sunroof relay (944 615 117 02) and put it in your G21 location. One could easily imagine the wrong relay shorting a circuit and popping a fuse like you are seeing, so I'd say there is a reasonable chance the right sunroof relay will fix the issue.

Here’s my vin: WP0AA0943GN453856

That is quite strange. So i actually found that my sunroof relay is in the g16 spot which is not for the sunroof so when i moved it to the g21 spot to try it the sunroof still doesn’t work. i ordered a complete used set of relays for this car for 95 bucks so we will try that and then i’ll have all the right relays in the right spots and be able to start identifying and isolating the problem. In the image of the relay box it has a relay in the g21 spot aswell so maybe Porsche just has a discrepancy on relay layout??

G16 for the buzzer/gong that goes off when you have the key in the ignition and the door open. It's the relay with the little speaker-grille opening on the top for sound. I don't see one in your pictures though. I'm assuming your car does not have a warning buzzer right now? Someone must have gotten mixed up and/or started plugging in random relays for some reason. Keep in mind there are lots of things beyond that relay that can prevent the sunroof from working. When you plugged the sunroof relay into G21, did the fuse 8 blow like it did with the ABS relay. If not, that would at least confirm the ABS relay was the cause of the fuse-burning short. Do you know about Clarks? If not, see here for sunroof diagnostics:

http://www.clarks-garage.com/shop-manual/body-03.htm

Your VIN is an '86 model and there is most certainly a disconnect between the factory manual/schematic and your fuse box. If it was an isolated incident, I'd wonder if someone swapped a latter fuse box into your car, but others have reported similar discrepancies. I think you have to work on the belief that g21 is the sunroof relay. If a new relay doesn't fix it, I'd go through the other diagnostics and, to just to confirm, I'd probably ohm out the G21 socket to the rest of the sunroof circuit just to make sure.

When i put the sunroof relay i have into that spot the fuse no longer blew, so i think the abs relay was causing that issue, but i’ll check out that clark’s garage information later this week once my new relays arrive.

[dr bob]

The fuse box almost undoubtedly has a part number on it. See if you can find it and maybe it's a clue to the differences.