Voltage drop between ignition switch and starter solenoide

[Ian928]

Hello all,

After first installing a starter relay, then installing new brushes and new relay, I hoped my stag would start for the coming years. No such luck! It have developed from not starting on the first try from time to time, then more troublesome to yesterday when I almost could not make it start. I suspected the ignition switch, so did the usual jiggling of the key, and sometimes it seemed to do the trick and the car started. But sometimes I could hold the key still in the start position and after a while the car started!

I went under the car and at the back of the ignition lock with the voltmeter today and did these measurements:

Big Red wire on back of the ignition lock: stable 12,5V
Big red and white wire on back of ignition lock when key turned to start position: stable 12,5V
Big red and white wire connector to starter solenoid: fluctuating 1-9V
Checked the relay against the big red wire on the starter solenoid: clicking
Tried to bypass the starter relay with the original setup: no start

Sooo I think there is something going on between the ignition switch and the solenoid. Any suggestions where to start looking? Are there any connectors between the ignition switch and the starter. When I think about it now there is one not far from the ignition switch, I will go and check this now.

If anyone have any suggestions I am happy to hear!

[Lingen]

Ian.
There is a particular multi-pin connector in the wiring between the starter motor and the ignition switch which is in a wiring loom hanging close to the bulkhead below the fuse box, where it can get pretty dirty. On an automatic transmission, a lead connects from it to the gearbox loom to only allow the starter motor to operate in Park or Drive. On a manual car, this lead merely loops back through the connector to provide a continuous supply. I suggest that you pull the connector apart, and clean it with solvent, and try to get the contacts free of dirt and corrosion. This might sort out the problem.
Mike.

[Ian928]

Thank you Mike!

I just returned from the garage where i took the multiplug on the steering column apart. I cleaned it, and plugged an unplugged it a few times, and this apparently did the trick! I now got 12V at the starter solenoid (or in my case the starter relay).

Another thing I forgot to mention is that I measure 0,2 - 0,6V from the ignition lock to the starter also in the run position. Should I get a new ignition switch?

[Ian928]

Ian.
There is a particular multi-pin connector in the wiring between the starter motor and the ignition switch which is in a wiring loom hanging close to the bulkhead below the fuse box, where it can get pretty dirty. On an automatic transmission, a lead connects from it to the gearbox loom to only allow the starter motor to operate in Park or Drive. On a manual car, this lead merely loops back through the connector to provide a continuous supply. I suggest that you pull the connector apart, and clean it with solvent, and try to get the contacts free of dirt and corrosion. This might sort out the problem.
Mike.

Mike, I will look for this multiplug. Do I understand it correct that this is in the engine bay and not inside the car? It may be placed differently on my car because it is LHD though, there are some differences.

[Lingen]

Ian.
It is in the engine bay down near the chassis rail on a R.H.D. car, and although I cannot be sure, I would expect it to be there on your's as well. It is where the bulkhead turns under to become the floor near the transmission tunnel.
Mike.

[trunt]

Ian.
It is in the engine bay down near the chassis rail on a R.H.D. car, and although I cannot be sure, I would expect it to be there on your's as well. It is where the bulkhead turns under to become the floor near the transmission tunnel.
Mike.

Its the connector that goes to the gearbox. On automatic cars the white/red wire also goes through the gearbox (if you have an Auto you will need to check the inhibit switch there as well) , on manual cars it still goes to that plug but just loops back on the gearbox side.. On my LHD federal the connector is on the LHS of the car, near the starter.