Wiring

[dooce]

I have an issue with the wiring to the ignition switch/wiper stalk. If I have the key on, engine not running, and move the wiper switch to the fast position, it engages the starter. Ive taken the steering column cowling off and took a look at the wires. The only damaged wire is the black w/ yellow wire that goes to the ignition switch. It was melted and I have since soldered in another wire from a breaker. When I did this, I cut it off after a bit of undamaged wire. I have also replaced the ignition switch. It still happening, any one have any ideas?

The car has the intensive wash fitted as well. Im going through the wiring diagrams now, hopefully find something they both share.

[shedrool83]

The black/yellow is the starter solenoid so that has been the problem if it had melted.
The ignition switch was more than likely faulty.

[dooce]

I edited the original post when you were responding, ignition switch didnt fix it.

[dooce]

I should also mention it is a 88 325 manual touring. The wipers do not come on in Fast when put there, it only engages the starter.

[Brianmoooore]

The car has the intensive wash fitted as well. Im going through the wiring diagrams now, hopefully find something they both share.

NOTHING common to the ignition switch/starter circuit and the rest of the column stalks.
The only thing that can cause the starter motor to engage is to apply a relatively high current at 12 volts + to the black/yellow wire (or plain black wire where it leaves the ignition switch.)
Concentrate on what damaged the black/yellow - it would have to short to earth somewhere between the ignition switch and the starter motor.

[dooce]

OK thanks. I had a standard (non intensive wash) wiper stalk so put that in just to see if anything changed. Now neither the ignition switch or the wiper switch will engage the starter, but the wipers work on fast mode.

EDIT:

I've found an intensive stalk and put that one in and its acting the same as above. Wipers work on all settings but the ignition switch does not, even with the key.

[dooce]

OK so I've found the black with yellow wire burnt all the way to the c101. I'm going to pull the dash out and replace the wire from the c101 to the ignition switch. Anyone know which pin extractor and pins that I will need? I cant seem to find them on realoem. I've jumpered the wire already and all my problems are gone. Any idea what could of caused this to begin with? I would hate to replace the wire just for it to happen again.

[Brianmoooore]

If it's burnt all the way to the C101, then it will be burnt into the engine loom as well. The wire goes to the starter motor with a branch to the diagnostic socket.
Sounds like the yellow/black has melted into other wires across behind the dash, so it'll be a good idea to remove the dash (relatively simple job on an E30), unwrap the loom, repair/insulate as required, then re wrap with cloth loom tape.

[dooce]

Yes, thats the plan. Do you think a faulty ignition switch was the culprit?

[Brianmoooore]

Yes, thats the plan. Do you think a faulty ignition switch was the culprit?

Definitely not. The culprit will be as far from the ignition switch as the damage extends.

[dooce]

Wow ok. So if the damage goes to the starter, you think it was probably that then? Is there not something to prevent this from happening?

[Brianmoooore]

If someone had connected the black/yellow wire to the smallest stud on the starter motor, and then held the key in the start position for some time, it could possibly cause damage like this, but apart from that, it would have to be a short circuit to earth, and again, the key would have to be turned for a time by someone with no sense of smell.
No fuses in the circuit.