1972 Back Up Lights

[VW Phi Delt]

I am almost ready to put my 72 Super Beetle Convertible back on the road but I have an issue with the back up lights. According to the wiring diagram, the power for the back up light switch comes from #15 on the coil. I have that wired and an 8 amp in-line fuse (recommended from the new wiring harness instructions) in place but i keep blowing the fuse. Anyone have any ideas?

Thanks

[68IHscout]

Are you going straight to the lights from the coil? Do you know where youre back up switch is mounted ? if you are not bypassing the switch on the fron of tranny , I would recheck all Wiring for the back up lights ...

[VW Phi Delt]

Sorry, the wire from the coil goes to the back up switch on the trans axle. Then it is wired from the switch to the back up lights. I crawled under the car and had voltage to the switch with the car running and in reverse but no voltage coming out of the switch. I would say that the switch is probably bad but I don't know if that would be the reason why the fuse keeps blowing.

[BugMan114]

It's wired from the positive on the coil, to the switch on the trans. Then from the switch on the trans, it goes back into the engine compartment, and gets T'd into both tail light housings. Check all the wiring, especially where it goes into the engine compartment. If that grommet is gone, the wires may have rubbed raw. And check where they exit the engine compartment, and go into the tail light housings. I'd also check to make sure you pull the tail light cover and reflector housing out to make sure the contact the wire is plugged in at the bottom, isn't bent, causing it to touch the reflector housing it's plugged into, or the fender.
_________________
1974 Super Beetle: Custom resto in progress
1972 Super Beetle: Daily Driver
1971 Std. Beetle w/ 1929 Mercedes Benz Gazelle kit
1960 Baja Bug
1969 Baja Bug
Sand Rail- Homemade
Sand Rail- FUBAR

Aircooled Airheads

Why the hell do they call it a gland nut. its obviously a big fat bolt!!!

[BugMan114]

[VW Phi Delt]

Thanks. I'll recheck all of that. I know the grommet is there and all of the wiring is new as I have installed a new wiring harness. Can't say for sure that something isn't touching somewhere or that I have a good ground (but all of the other lights work). Just wanted to make sure that I wasn't missing something and that the back up lights did get the power from the coil through the back up light switch. It's kind of dicey laying under the car with it running and your wife operating the clutch and what not while your trying to figure stuff out.

[VW Phi Delt]

I will check the switch with my meter and see what happens

[BugMan114]

Oh god, the car doesn't have to be running . Just turn the key on, and have it in reverse. It will still get power.
_________________
1974 Super Beetle: Custom resto in progress
1972 Super Beetle: Daily Driver
1971 Std. Beetle w/ 1929 Mercedes Benz Gazelle kit
1960 Baja Bug
1969 Baja Bug
Sand Rail- Homemade
Sand Rail- FUBAR

Aircooled Airheads

Why the hell do they call it a gland nut. its obviously a big fat bolt!!!

[VW Phi Delt]

Been 27 years since I messed with a bug. You'd think a guy might get a little smarter with age. Guess not. have a '74 Thing that I want to get started on if I don't kill myself with this one first!

[VW Phi Delt]

Finally had some time to on these backup lights this weekend. After testing to make sure that the lights worked in the tail light housing by hooking them up direct to the coil, I pulled all the wiring and checked it. Everything looked fine so I hooked the back up lights externally to the coil (and through the inline fuse I installed) without going through the switch. Wouldn't you know, they came right on when I turned the key on. I then externally hooked everything up through the switch and sure enough, they worked. Put it all back together and I had backup lights.

Saturday morning I checked the backup lights and I had nothing. At this point, I'm feeling that the switch has an issue. I'm still waiting for a new switch to come in. Regardless, I hop in the car with my son and we take a short 2 mile drive up to the football field for youth football sign ups. About 30 minutes later, I try to start the car and it fires but immediately dies. We hang around for another hour and the car fires right up and runs. I get home and park it. Twenty minutes later, it won't run. So, we push it back in the garage. About 5 hours later, I get in it and start it. Idles fine, don't here anything out of the ordinary. I turn the car back off and try to restart it and once again it won't fire.

I'm getting plenty of gas to the carbs. I still don't have backup lights and yesterday I couldn't get it to run at all. Is it possible that I have messed the coil up because of the backup lights?

Any help would be greatly appreciated.

Thanks

[Cusser]

Unplug the wire to the back-up lights from the coil. Now try to run the engine.

You may have an intermittent short in the wires up to or back from the switch on the transmission.
_________________
1970 VW (owned since 1972) and 1971 VW Convertible (owned since 1976), second owner of each. The '71 now has the 1835 engine, swapped from the '70. Second owner of each. 1988 Mazda B2200 truck, 1998 Frontier, 2014 Yukon, 2004 Frontier King Cab. All manual transmission except for the Yukon. http://www.thesamba.com/vw/forum/album_page.php?pic_id=335294 http://www.thesamba.com/vw/forum/album_page.php?pic_id=335297

[VW Phi Delt]

I tried that late Saturday afternoon and then I got the engine to run. As soon as I shut the motor off, I couldn't get it started again. With or without the backup light wire on the coil.

[scrivyscriv]

Sounds like:

1) Vapor lock (make sure your fuel line isn't resting on the left heat exchanger)
2) Intermittent coil fault (Ohm out the coil to check specs) or
3) No/restricted fuel flow to carb jets.

Check your fuel shutoff solenoid, maybe you accidentally bumped the wire loose while messing with the coil. While you're there, check the other side of the carb and make sure you didn't jack up the choke wire or bump the choke coil out of position. Choke may be sticking closed or fuel solenoid cutting fuel flow!


The switch is either open or closed, so if bypassing the switch gave you working reverse lights, the switch is bad. I would not worry about having damaged the coil. Do you have the coil terminals hooked up to their correct respective wires?
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[VW Phi Delt]

Well, I'm not an engine guy or an electrician. I'm more of the body repair, paint and put everything back together guy. I will check the position of the fuel line to make sure it is not on the heat exchanger. I don't think it is vapor lock as the motor won't run after sitting for a day. This is an 1835CC dual carb set up. There is no choke and no fuel shut off. I will check the Ohms out on the coil. I think I can figure that out. I pulled the breathers off of the carbs and I get plenty of fuel out of the jets when I manually throttle the linkage. Doesn't mean the fuel pump is working correctly though.

[scrivyscriv]

Well, dang.

You might want to start a new thread with just the no/hard start issue so people will be a little more helpful, and continue on here with a followup on the reverse lights.
I've found that electrical-related posts generate a lot less response traffic than just about anything else.
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[VW Phi Delt]

Thanks for the advice. I'll start a new post tomorrow after i check the Ohms and fuel line position tonight. I just thought this issue might be related to the backup lights because they run through the coil on this 72.