Electrical problem, need advice

I have a 1981 Rabbit-D. It runs great, but the other day after turning it off, it would not start, almost like taking a battery cable off. No clicking or indications of a weak battery. However, when I run a wire from the injection pump to the battery, everything works fine and it starts.

I am guessing the injection pump relay but I cant find it. I know its under the dash near the steering wheel and not on the fuse panel. Anyone had similar problems? Thanks

there is no injection pump relay. first check that the blu/blk wire is not frayed where it passes through the firewall, if it is then you just need to pull another wire. the fuel shutoff solenoid on the injection pump gets power directly from the ignition switch. a blue wire with a black trace (blu/blk) attaches to the black wire that comes off of the ignition swich. look under the dash and find the wire harness that goes up toward the steering column; on this section of the wire harness is a black multiplug connector on the right side of the fuse panel, you should find the blu/blk wire there. check to make sure that all of the connections are good (i've herd of some of the pins coming out of the connector block, and corrosion is a likely culprit. unplug the plug and clean it with some electrical contact cleaner or a pencil eraser if you have the patience. make sure ALL or the pins are reconnected when you put the plug back togather as some like to push out of the plastic case). if the blu/blk wire is not there then it taps the black wire on the back of the glow plug relay (the glo relay is at the top of the fuse panel). get a cheap voltmeter and do some continuity tests (remove the battery first). terminal 86 on the glo relay should have continiuty with the black lead from the ignition swich and the fuel shutoff solenoid as they are all on the same circuit, i'm just not absolutely sure where the blu/blk wire taps the black wire from the ignition. i think the connection is made on the ignition swich side of the black multiconector under the dash. try there before you go behind the glow relay (you may have to remove the wraping on the harness, but only if you see the blu/blk wire at the multiplug). as always, look for burnt, bare, and frayed wires; also feel the wire to see that it is easily bent and does not feel "crusty" inside. it will probably be best to find where the blu/blk wire taps the black ignition wire and work toward the injection pump, provided the connection at blk-blu/blk is good. i can provide more indepth information if you need it.

recap:
1. check multiconnector for blu/blk wire
2. if present make sure the pins did not back out of the plastic connector
3. if present clean pins inside of the multiconnector
4.if present find where blu/blk taps into blk from ignition sw.
5. trace from tap point to fuel solenoid

6. if blu/blk is not present in the multiconnector look behind the glow plug relay socket (it comes off of the fuse panel for easy access)
7. find where blu/blk taps the solid black wire, after checking the integrity of the connection trace it to the fuel solenoid

Or.......

Check starter/ignition fuze first
Also, it is posible to have a bad ignition switch itself.

Check the fuze before you go following wires.

there is no starter ignition fuse; there is a fusable link in the circuit before the ignition swich, but if the engine cranks then this fusable link cannot be the problem. in fact an '81 diesel rabbit will start and run without a single fuse or relay on the fuse block (however, don't let it run for too long), to include the glow plug relay, but it is EASIER to start with the glow relay present. there is a decent chance that the ignition switch is defective.

I have been driving for months with a wire connected from the battery to the injection pump so I am trying to fix the problem.

I checked and I have continuity between the black wire in the wiring harness at the ignition switch and the end of the blu/black wire at the injection pump.

Now I am attempting to replace the ignition switch. The manual is not clear on the location for drilling a 3 mm hole to remove the ignition switch. Any ideas or anyone with better pictures? Thanks

1981 Rabbit-D

There will be one or two heavy sized rivets holding the switch to the steering column. You need to drill those rivets out. Usually you can just drill the heads off and then push the posts out the other side. Don't drill all the way through, won't have anything to push on.