Club 80-90 Forums

My problem has reoccurred! Again I have no 12v at the coil but when I run a separate 12v feed from the battery to the coil, the engine starts immediately. There is a single spade connector in the black plastic wiring box in the engine bay just in front of the coil. This has the single black wire coming from the ignition switch joining to a double black wire which seems to go to the coil. If I disconnect this, then the feed from the ignition switch shows around 5-6V which is strange as I would have expected battery voltage. Strangely, if I reconnect this connector, you would expect to see the same voltage at the coil, but there is 0v there.

None of this makes any sense to me. I have done a continuity check on the wire from the ignition coil to the coil, and it is fine. I can only assume that there is a resistance somewhere in the line which is causing a voltage drop.

SO as a recap, I would expect to see battery voltage at the coil when the ignition is switched on, but I see 0v at the coil, and only 5-6v at the connector just before the coil. I don't see why there is a double black wire going to the coil. I assume there is another connection from this somewhere in the engine bay wiring but I haven't found it yet. The Haynes manual is not much help here.

According to the Haynes manual, the black wire from the ignition switch plugs into the back of the fuse/relay panel on plug 'A' and then exits on plug 'D' and goes to the engine bay. Could the fuse/relay panel be faulty?

I have a few more continuity checks to do, but if anyone has ever had anything similar happen, I would love to know!

Problem solved! I traced the wire from the ignition switch to the fuse/relay panel and it was fine but the one out of the connector D had been cut and was connected to a suspicious grey wire running with a few other wires through a hole in the front of the dash. Removing the headlamp grille and a plastic cover, I found an after market alarm immobiliser with very corroded connections! Once bypassed, all returned to normal. I am pleased I have actually found a fault as I hate electrical problems which heal themselves!

I hope this post has been interesting for anyone who has been reading it.

Were you aware that an immobiliser was fitted?

I had no idea. The previous owner probably didn't even know! He never had any key fob for it. I suspect it was fitted sometime when the van was young in the 1980's (made by Quantum alarms which I struggle to find any info on from the web!), probably never got used much, key fobs lost and just forgotten about over time.