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Mon Dec 08, 2003 9:47 am

I think my switch might be bad. On the solenoid I touched a wire between the terminal from the switch and the one from the battery and the engine fired. When I turn the key, the alt & oil lights come on, radio works, etc., but nothing happens with the starter. How can you tell if this is a bad switch, not enough current, or probelm with the solenoid?
Also, the PO said he had to replace the switch. What could keep making it go bad if this is my problem? Also, I was going to try to bridge the wires in the switch to see if that was the problem, but when I pull off the pigtail there are several connections. I know VW was inconsistant in wiring colors but would it make sense that the large black is the ground and the two large red one are to the solenoid? I tried grounding the black terminal and connecting the two red ones. All I got was a slight clicking sound.
Thanks,
Mike

Mon Dec 08, 2003 10:11 am

Black is NOT ground on a VW... it is hot 12V. the black wire from the ign switch is the 12v feed to the coil and other systems that get power with the key on.

the big red wires, one is the 12V into the switch and the other ( usually red with a black stripe) is the one that goes to the starter solenoid when you turn the key.

Get a test light and hook it to the wire that plugs onto the solenoid, have a helper turn the key, if the test light goes on, then the switch and the wire to the starter are good ...
and you have a solenoid/or ground cable/other problem.

if the light does not come on, then use the pointed end of the tester to pierce the wire right out of the switch and see if it is getting that far. if it is then you need to trace the wire and find the fault/ broken connection and or maybe even run another wire to confirm that is indeed what it is.

if you haven't already, check your ground connections/ battery connections, and the tranny to frame ground strap. sometimes adding another ground cable directly from the battery to the lower mounting nut on the starter itself does wonders for the intermittant start scenario.

Mon Dec 08, 2003 5:22 pm

Thanks. Good stuff. I didn't think to break out the test light.
Pierced the large red wire with the black stripe coming from the switch without turning the key, no juice, turned the key, light came on. This tells me this should be the one that runs to the solenoid and the switch is probably good. Crawled under the car and tested the terminal on the solenoid with the battery connection to confirm I had a good ground on the test light then tested the connection from the switch on the solenoid while a friend turned the key, no juice.
This tells me the switch is probably good but I'm loosing connection somewhere along the way. Sooooo...
What is the general path of this wire? It's dark outside now, but best I can tell it turns back up towards the instrument panel. If someone knows the general path of this wire and where the connection points are it might help me find the breakdown.

On what may be a side note.... there are a multitude of small wires connecting to the solinoid, the one with a femal spade terminal that is the one from the switch, one with a plastic case over the connection, and in my case a loose green frayed one. What are these other two? I don't think the loose frayed green one is the source of my problem since the bus was starting fine a few days ago. Just wondering what these are.
Thanks,
Mike[img][/img]

Mon Dec 08, 2003 5:29 pm

Sorry, I was trying to imbed an image in the post. Here is a photo of the wires.
http://images.thesamba.com/vw/gallery/pix/129183.jpg

Mon Dec 08, 2003 5:56 pm

What year specifically is your bus?

were you doing any other work to the bus, electrical or otherwise, under the dash any? in the engine compt area?

If I remember there is at least one plastic "juntciton" where the wire from the switch connects to the wire going twords the rear to the starter.

Mon Dec 08, 2003 11:31 pm

It's a 76. I recently installed a radio but It started fine for a few days afterwards. Probably not the best approach, but I arbitrarily found two wires with the test light for the power and the memory wires. I thought this might be related so I checked both wires that I tapped and they are both hot before and after the splice. I even tried disconnecting both but no dice. I guess I could take your suggestion and run a long wire directly from the switch. If that works I know I just have a break in the connection somewhere and can start trying to follow it into the abyss.
Oh yeah, one other thing. There are a bunch of wires and two battery terminal connections dangling loose on the left side where the second battery is supposed to go. I had to move those around recently but didn't alter anything that I can think of. I'm not sure how they play into the picture, but are the only other thing I can think of that I touched.