Electrical Update

Gotta love that wiring . . .
davery
Posts: 804
Joined: Sun Apr 15, 2012 8:51 pm
Your car is a: 1985 Spider
Location: Ohio

Electrical Update

Postby davery » Sat May 20, 2017 1:30 am

1985 Electrical update – All rear lights and gauge lights are now working, but still no lo beams and front side markers. Hi beams (and hi beam indicator light) and rear side markers are working. I’m not sure if this is one issue or two separate issues. The headlight switch was bent (and was very finicky) when I bought the car, so the issue could be the column switch. This all began after I detailed the engine bay after wrapping the wires in a wire loom. I’ve since removed the wire loom and cleaned the grounding pods in the engine bay, but still no lo beams or front side markers.

A few questions-is the power to the lo beams supplied by both fuse E and F? It looks like a gray/black wire from fuse E supplies the driver’s side and a gray/yellow wire from fuse F supplies the pass side. Is this correct? If this is true, then it looks like the first point both sides connect is the relay. I think I can hear the relay clicking when I turn on the lo beams. Also, the green headlight indicator light is working, but I can’t find the wiring for this the diagram. Any idea what fuse this is?

The first point the front side markers meet is at C17, where they also meet the rear side markers. Since the rear side marker are working, it would appear this connector is getting power. I haven’t checked the bulbs and I guess it is possible both went bad at the same time.

I would think if the column switch is bad and the rear side markers are working then the front side markers should be working. It appears both the front and rear markers are supplied by the same wire and split at C17.

Even though OEM column switches for an 85 are non-existent, there are reproductions that are close (but expensive). If I was sure it was the column switch I would buy a reproduction switch. Is there any way to test the switch to make sure?
Don Avery
Dayton, OH/Sarasota,FL
1985 Pininfarina
2011 Eos
2012 Mercedes E550 Cabriolet

aaalbedo
Posts: 45
Joined: Mon Jun 21, 2010 7:37 pm
Your car is a: 1984 Pininfarina
Location: Gunbarrel, Colorado

Re: Electrical Update

Postby aaalbedo » Wed Jun 07, 2017 11:41 pm

Here's the '83 manual.

https://www.dropbox.com/s/s71xf2t7jb3ym ... l.pdf?dl=0

Brad Artigue has the '85 manual on his website.

The '83 manual on page 100 shows you are correct about the low beams being split between two fuses.

I just opened up the column switch on my '84 and cleaned contacts on the parking light switch and wiper controls. That restored my tail lights and instrument lights, but then my turn signals stopped. So I'll be back in there this weekend. Contact cleaner spray cleaned up all the grease in there. The switch assembly seems to be solidly built and cleaned up pretty well and it was pretty easy to open and reassemble. hopefully the turn signal part will be the same.

When the parking light switch (rocker on top of the steering column) was dirty and disabled my taillights, the instrument lights and all four side markers were out too. So your side marker issues won't be the column swtich; start with grounds.

Larry
1984 pininfarina, Honda S2000 seats, daily fair weather driver
2006 BMW 330 CIc, sensible winter convertible

davery
Posts: 804
Joined: Sun Apr 15, 2012 8:51 pm
Your car is a: 1985 Spider
Location: Ohio

Re: Electrical Update

Postby davery » Sat Jun 10, 2017 7:57 am

aaalbedo wrote:Here's the '83 manual.

https://www.dropbox.com/s/s71xf2t7jb3ym ... l.pdf?dl=0

Brad Artigue has the '85 manual on his website.

The '83 manual on page 100 shows you are correct about the low beams being split between two fuses.

I just opened up the column switch on my '84 and cleaned contacts on the parking light switch and wiper controls. That restored my tail lights and instrument lights, but then my turn signals stopped. So I'll be back in there this weekend. Contact cleaner spray cleaned up all the grease in there. The switch assembly seems to be solidly built and cleaned up pretty well and it was pretty easy to open and reassemble. hopefully the turn signal part will be the same.

When the parking light switch (rocker on top of the steering column) was dirty and disabled my taillights, the instrument lights and all four side markers were out too. So your side marker issues won't be the column swtich; start with grounds.

Larry

I have cleaned all the grounds I know of. Since the marker lights are only on when the headlights are on, wouldn't that mean the headlight switch also controls the marker lights? That being said, I have no clue why the rear markers work and the front do not. When I get home from vacation I want to run a power wire directly from the battery to the headlights. Theoretically, this should tell me where the issue is (or at least get me closer).
Don Avery
Dayton, OH/Sarasota,FL
1985 Pininfarina
2011 Eos
2012 Mercedes E550 Cabriolet

davery
Posts: 804
Joined: Sun Apr 15, 2012 8:51 pm
Your car is a: 1985 Spider
Location: Ohio

Re: Electrical Update

Postby davery » Sat Jun 10, 2017 7:59 am

davery wrote:
aaalbedo wrote:Here's the '83 manual.

https://www.dropbox.com/s/s71xf2t7jb3ym ... l.pdf?dl=0

Brad Artigue has the '85 manual on his website.

The '83 manual on page 100 shows you are correct about the low beams being split between two fuses.

I just opened up the column switch on my '84 and cleaned contacts on the parking light switch and wiper controls. That restored my tail lights and instrument lights, but then my turn signals stopped. So I'll be back in there this weekend. Contact cleaner spray cleaned up all the grease in there. The switch assembly seems to be solidly built and cleaned up pretty well and it was pretty easy to open and reassemble. hopefully the turn signal part will be the same.

When the parking light switch (rocker on top of the steering column) was dirty and disabled my taillights, the instrument lights and all four side markers were out too. So your side marker issues won't be the column swtich; start with grounds.

Larry

I have cleaned all the grounds I know of. Since the marker lights are only on when the headlights are on, wouldn't that mean the headlight switch also controls the marker lights? That being said, I have no clue why the rear markers work and the front do not. When I get home from vacation I want to run a power wire directly from the battery to the headlights. Theoretically, this should tell me where the issue is (or at least get me closer). Do you have any pics of when you opened up the column switch?
Don Avery
Dayton, OH/Sarasota,FL
1985 Pininfarina
2011 Eos
2012 Mercedes E550 Cabriolet

aaalbedo
Posts: 45
Joined: Mon Jun 21, 2010 7:37 pm
Your car is a: 1984 Pininfarina
Location: Gunbarrel, Colorado

Re: Electrical Update

Postby aaalbedo » Sat Jun 10, 2017 6:45 pm

There are two circuits that power the parking (marker) lights, and both run through that little rocker switch on top of the steering column. There is a hot wire in there so that when the rocker is centered, the parking lights will turn on without the key. When the rocker is flopped over to either side (there's a mechanical cancel similar to the turn signal cancel that moves the rocker away from center when the wheel turns) then the parking lights are powered from the light switch through a set of contacts in that rocker.

So if the rocker contacts are gunked up like mine were, it can open the circuit that the light switch uses and you won't have parking lights. BUt you lose all eight lights and the indicator in the tach when these contacts are open, so your problem seems to be elsewhere.

I just opened mine up again and cleaned up the turn signal contacts... now I have front turn signals, and the single indicator in the tach is working, but neither of my rear turn signals is. Time to look at those grounds again I guess, both at the chassis and at the taillight circuit board.

lw
1984 pininfarina, Honda S2000 seats, daily fair weather driver
2006 BMW 330 CIc, sensible winter convertible

aaalbedo
Posts: 45
Joined: Mon Jun 21, 2010 7:37 pm
Your car is a: 1984 Pininfarina
Location: Gunbarrel, Colorado

Re: Electrical Update

Postby aaalbedo » Sat Jun 10, 2017 8:25 pm

Don:

I didn't take photos while I had the switch apart, but I have a spare so I'll take some photos of that.

In the meantime, you mention C17. Where is that connector? It appears that it is different than in the earlier cars. This wiring diagram for the 1984 shows that C17 is a six position connector in our cars, but I see references to C17 as a four position connector in the earlier models.

With my taillight assembly out, I can see that my turn signals are barely flashing so I have a big voltage drop somewhere along the way.

lw
1984 pininfarina, Honda S2000 seats, daily fair weather driver
2006 BMW 330 CIc, sensible winter convertible

aaalbedo
Posts: 45
Joined: Mon Jun 21, 2010 7:37 pm
Your car is a: 1984 Pininfarina
Location: Gunbarrel, Colorado

Re: Electrical Update

Postby aaalbedo » Sat Jun 10, 2017 9:12 pm

Here are some photos of the column switch.

Two connectors. I had to remove the instrument panel to get to mine. One is C26 and I think the other is C27.

https://www.dropbox.com/s/861n6d8r1ce65 ... s.png?dl=0

https://www.dropbox.com/s/x75e3geft6lhh ... s.png?dl=0

Rear of column switch assembly. The rocker switch is at the top, and this one has been bypassed.

https://www.dropbox.com/s/opgj0s2pqdbr3 ... r.png?dl=0

Front of switch assembly.

https://www.dropbox.com/s/zs20gs4p5mfu7 ... t.png?dl=0

The screwdriver is resting on one of three tabs that you have to pry inward to release the ring that rides on the horn brushes. You have to release each tab and rock the ring a bit, then after it moves out a bit you have to pry each of them again to remove the ring.

Behind that ring is the black steel plate with four SS screws. Remove that plate and that releases the rocker switch. This one is missing some parts so it won't be helpful to open it further. You can see a slot below the P; there is a small plastic part that has a post that sticks out through this slot. There are also a couple of springs with detent balls so disassemble carefully.

The turn signal switch to the left is held on by four screws. There is a spring loaded assembly inside the cap. You don't really have to go into that, so hold the plastic cap down while you remove the screws. Then keep the turn signal arm pressed against the cap to keep the assembly together. I used a small spring clamp to hold the cap and arm together. You can clean all contacts without disassembling that. I did end up taking that assembly apart; it's a pain to get back together. There's a white plastic part with a post on the back that goes through the loop on the end of a small sping. That post then goes through a slot in the back, and there are two plastic parts in between, held together with a spring. You have to spread those black parts apart to let the white part drop into place. Then hold it all together with the arm. Once it's all back together it's pretty easy to put it back into the main assembly and hold it all down while you put in the screws.

lw
1984 pininfarina, Honda S2000 seats, daily fair weather driver
2006 BMW 330 CIc, sensible winter convertible

davery
Posts: 804
Joined: Sun Apr 15, 2012 8:51 pm
Your car is a: 1985 Spider
Location: Ohio

Re: Electrical Update

Postby davery » Sat Jun 10, 2017 10:02 pm

aaalbedo wrote:Don:

I didn't take photos while I had the switch apart, but I have a spare so I'll take some photos of that.

In the meantime, you mention C17. Where is that connector? It appears that it is different than in the earlier cars. This wiring diagram for the 1984 shows that C17 is a six position connector in our cars, but I see references to C17 as a four position connector in the earlier models.

With my taillight assembly out, I can see that my turn signals are barely flashing so I have a big voltage drop somewhere along the way.

lw


I have not located C17 yet. I haven't. had a lot of time lately. I should be able to trace the wires and find this connector when I have time.
Don Avery
Dayton, OH/Sarasota,FL
1985 Pininfarina
2011 Eos
2012 Mercedes E550 Cabriolet


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