I recently had a major electrical problem that I finally fixed today, with the help of my friend Simon (who is visiting from Australia; I'm sure working on my Bus is exactly what he wanted to do while he was here :-)
The story:
Last Sunday, I drove the Bus to San Francisco Airport to pick up Simon. Bus ran great. We then dropped my wife off in downtown San Francisco before heading over to Berkeley to take some stuff to Ohmega Salvage. I noticed my turn signals were flashing sort of quickly, so I asked Heather to check for burned-out bulbs when we dropped her off. All lights were OK. So we drove over to Berkeley, and all was well.
After dropping the stuff off at the salvage yard, I go to pull out of a parallel parking spot back onto San Pablo, and when I rev the engine, the flasher goes "BZZZZZZT" and the CD player power-cycles. This symptom persists for a while, but goes away once we're 1/2-way back across the Bay Bridge.
At first I think I have a water-in-the-dash problem, since we had our first big rain storm of the year just the day before, and I had a windshield leak (which I have since fixed).
Fast-forward to Tuesday. I go outside to move the Bus to a different parking spot. I'm still having a bit of a cold start problem since the engine rebuild, and the Bus does not start after 5 seconds of cranking. So I turn the key to off, then to on, then to start -- nothing happens. Turn the key to off, then to on -- nothing happens. No lights, nothing.
Great, dead battery, I think. VOM across battery reads 12.7v, and a test at the FLAPS indicates it's OK. OK, so it's not the battery.
Simon and I trace the wiring diagram looking for problems. We determine that no voltage is making it to terminal 30 on the ignition switch.
We stop there, as we have other things to do, and a friend's wedding to attend.
Fast-forward to Sunday. We go back out to work on the Bus before the rain returns. We replace the ground strap on the battery for good measure, and the loop-terminal on the wire that connects the battery to the alternator. This does not fix anything.
So, we decide to check continuity between terminal 30 on the solenoid and the battery end of the positive strap. Open circuit. So, the problem is the battery's positive strap.
Simon crawls under the Bus to trace the strap while I wiggle it from the engine compartment. He determines that the strap is intact.
Simon and I trade spots so I can see what he is describing. While down there, I happen to notice a gleam as my headlamp bounces around. Here is a picture of what I saw. Note how the loop terminal on the battery strap is not over the post on the solenoid!
So, I pull the nut off the solenoid, loop the strap over the post, put all the other wires back, and tighten up the nut. Viola, everything works perfectly again.
What scares me is how long the connection might have been in this condition. I wonder if it happened when the fuel lines were replaced or when the engine was replaced.
In any case, the Bus is working again (and my cold start problem seems to be gone, too, but I did wiggle the wire on Temp Sensor 2, so there is a variable to consider; I'm planning on replacing Temp Sensor 2 the next time I get a break in the weather).