No gauges, wipers, turn signals

[deacon]

I've done the brakes, the cooling system and the carb and didn't think I had any real electrical gremlins to fight....Wrong! I have no functioning gauges, no wipers and no turn signals. There may be more, but I have not found them yet. The headlights, marker lights and the CLOCK work. It starts and runs fine. I know there probably isn't one magical answer, but I wanted to refer to everyones experience and get some idea of what people have found in the past. I have checked all the fuses for continuity and even burnished all of the connections in the fuse box. Hmmmm?

My 78" spider....The project that keeps on giving

[So Cal Mark]

checking the fit of the fuses is a good start. Have you checked them for power?

[deacon]

Mark, I have not checked for power coming into the fuses yet. I will start there tomorrrow night. Thanks

Dan

[mbouse]

the good thing about Spider electricals is that they stay fixed for a long time after you get them sorted out. getting them sorted out is time consuming at best. be glad you don't own a LBC.

1. always suspect a bad ground.
2. work on one circuit at a time.
3. just because a fuse LOOKS good does not mean that it is.
4. always suspect a bad ground.

of course, we know that the battery is good, and so is the charging system.

begin by removing the negative battery cable from the battery terminal. then remove all the fuses from the fuse panel. using 00 steel wool, clean the fuse contacts. pinch the contacts so that the clearance barely allows a new clean fuse to be inserted. set all old fuses aside and replace with brand new fuses of the correct amperage; save the old fuses for spares.

obtain a replacement negative battery cable about 16" long and add it as a secondary grounding strap between the engine block and the inner fender on the passenger side.

clean thoroughly the battery terminals and the battery cable clamps. replace the clamps to the correct terminals.

buy an inexpensive volt meter and check each fuse for current on both sides of the fuse. of course, you already have a wiring diagram, and have learned how to read it.

find the grounding pod for the malfunctioning unit, and clean / tighten the ground connections there. next, clean and tighten the connections at the failed unit.

using the volt meter, check the hot side of the unit that is faulty to ensure that power is being supplied to the unit. if there is current availble, add a temporary ground wire to the other side of the malfunctioning unit.

some of the most common issues, besides dirty, loose, or faulty grounds include... previous owner wiring screw-ups, accidental disconnecting of wires, inadequate fuse amperage or too much added to a circuit, and aging wires and connectors.

eventually you will be interested in such things as brown wire surgery and headlight relays... but that is later.

oh, did i mention that the ground connections frequently fail?

[deacon]

That's great, I love it.

Oh, and I think I might check the grounds......

[htchevyii]

The other day my hazard switch popped out a little, (I didn't put on the nut on for easy replacement, but it's there now) and blew the fuse for the gauges and brake and turn lamps. I popped in a new fuse, (a little crusty but unused) and still nothing. Wiggled it around a little, nothing. Drove home without lights. When I got home I checked both sides of the fuse with my meter and it was no good! Looked fine, but no workie. I popped in a copper contacted BMW fuse that I got from work and everything's fine! I've since replaced the rest of my fuses with the copper ones. The rest of my problems have been caused by:
Bad grounds
bad hazard switch
corroded light sockets

[mbouse]

trey brings up a good point. the hazard switch must be installed and functioning for turn signal lights to work properly, especially the round style hazard switches.

there are ways to wire around them, but in general... they must be present in the circuit for seemingly unrelated functions to work properly.

[deacon]

First evening to work on the issue and we had great success. I first identified the fuse (A) and checked the fuse (OK). Then I pulled the fuse box itself and low and behold, the PO had cut the pink feed wire to hook up the electric fuel pump. Well they did a very poor job of crimping and it had come apart out of sight. Simple fix, hooked the battery back up and started the car. Hey, I have a 1/2 tank of gas! The gauges now work as well. There are a few other little isues, but those will be easy to deal with as I get to them. At least now I can run the car for more than a minute and have an idea what oil pressure and engine temp are doing. Getting closer........

[mbouse]

well, hearing that the PO has violated the integrity of the factory wiring... be prepared for more of the same.

isn't it great when you solve a problem? glad to hear that you are moving up and on.

[rlux4]

Personally I am shocked to hear that not only did a PO chop some electrical, but on top of that, did a sloppy job of splicing!
Ron