17 replies to this topic

[mike.]

I have a 1986 city e with pre-engaged start motor/solenoid.

The following wiring issue I really need help with as today the mini just tried to burn itself, me and the garage to the ground! Wiring is not my strong point...

When my car came back from being welded/sprayed/engine set up, the guy said he couldn't find my 'ignition wire' to connect to my starter motor. So he installed another wire which was spliced somewhere in the steering column loom (into the white/red wire IIRC) and ran down to the starter - The car started fine. When this wire was disconnected the starter wouldn't turn. When I looked at it to try and find the original 'missing ignition wire' I saw a large brown/red wire with a large insulated spade connector on the end. This I assumed seemed like it was obviously the missing wire and that the guy hadn't looked very hard. So I connected it to the starter motor and tested the ignition - The ignition lights came on in the clocks so I left it at that.

Its now a few weeks since I did that and I never actually tried turning the engine over to test the wiring to the starter. So today I reconnected the battery, and turned the engine over - Just for a split second to check it was working - It did turn over but then I hear a crackling sound and see smoke pouring out of the engine bay! Luckily I have a dis-car-nect battery terminal which let me disconnect the battery in a few seconds.

Basically whats happened is, one of the wires which runs from the starter to a Relay in the engine bay looks as though its taken the full load of the battery. It is now toast and its insulation has melted away. Smoke was also pouring from the relay so that'll be toasted too.

I have obviously connected this brown/red wire to the wrong terminal on the starter and shorted this other brown wire out. I've stripped back all the loom and removed all the loom tape and it appears i've been very lucky and only managed to damage this one wire and slightly melt the insulation on a few others - But it was a scary moment to say the least!

I'm hoping somebody can tell me where i've gone wrong with this starter wiring from the following pics and also tell me which other (if any) wires I may have also damaged in the process.

Here is how my started was wired:



You can see where i've connected the red/brown wire (and the other empty terminal it could have connected to) and also the brown wire which is damaged.

This is the state of the wire:







and it carries on this way right up the loom and to this relay:



I stripped the tape back and found this little 'splice' which includes the large gauge wire which melted and seems to have 2 other brown wires spliced into it which carry on towards the bulkhead - Is this right or another previous owner bodge?



Can anybody see where i've gone wrong? The haynes isn't much help in this situation and I don't want to just start swapping wires around any which way as thats how this happened in the first place really!

Thanks in advance

[lrostoke]

The brown/red wire does go to the starter solenoid, but looking at the wiring there does look like some messing as gone on.

You have 2 large cables going to the solenoid, there should only be one coming direct from the battery.

The starter solenoid shouldbe wired

large cable from battery plus all brown wires connected to threaded terminal

brown/red wire goes to top seperate large spade connector.

the brown/red goes back to the starter relay

the starter relay should be 4 wires,
black earth ,
white/red from ignition switch ,
brown from starter relay connection (perminant 12v live)
brown/red goes down to solenoid.

looking at the melted wires it looks like one of the brown wires as melted, these are perminant 12v lives, so the melted brown as dead shorted somewhere. does the melting stop at the relay, possible some sort of dead short inside with the black earth connection.

Edited by lrostoke, 10 November 2011 - 10:22 PM.

[charliedurrant]

I'm wiring one up tomorrow but have a side mounted solenoid aswell. I'll post a pic up anyway.

Bad luck though...

Charlie

Edited by charliedurrant, 10 November 2011 - 10:26 PM.

[mike.]

Thanks for the help. I should have mentioned earlier - The second large cable (the one wrapped in tape) running from the threaded terminal is a feed to my second fuse box i've fitted so that can be ignored as i'm pretty sure that can't be creating the issue.

All melting/damage stops at the relay and goes no further. The red/brown is fine and not damaged, its just the thick brown wire which goes from the threaded terminal to the relay which has melted.

Have I put the red/brown on the correct terminal?

Or is this just down to the relay itself?

Edited by mike., 10 November 2011 - 10:29 PM.

[lrostoke]

considering the brown/red isn't damaged I'd go with a short in the relay.

the brown/red does look to be in the correct place.

is the black wire to the relay damaged ??

[mike.]

No i'm pretty sure that was ok, I just remember the brown wire being melted along its length.

So if this is just a fault with the relay, does that mean I can just replace the relay and the length of damaged brown wire and thats it?

What sort of amp wire should I replace the damaged brown with?

[mike.]

Just been looking at my haynes manual and realised my manual only goes up to '85 and my cars '86, so no wonder I can never make out the wiring diagrams!

The starter relay on my car has 5 wires not 4 and my dad (the wiring expert of the family) is trying to figure out whats gone wrong but can't because the wiring diagram i've got doesn't show a start relay anywhere.

Just wondering if somebody can scan the wiring diagram out of their haynes manual for a '86 onwards car for me? I'll be buying a haynes which includes my car, but I can't be waiting a week for postage on that just to fix this problem

Anybody got one they could scan for me?

[charliedurrant]

Is the attachement okay? It's a large file so eats my upload space - so I will delete once you have it....

Attached Files

•  wiring-diagrams-84-on.pdf   1.44MB   112 downloads

[mike.]

Thats great!

Thanks so much. I'll study it after tea and no doubt be back on here with more questions lol

[mike.]

Ok, its been a whilst since I started this thread but I ordered some bits from autosparks and sorted it out yesterday. Just got a couple of questions and hoping someone can confirm i've done this right before I try it and set the loom on fire again...

Basically heres my starter motor. The big spade connector at the top - Thats where the large brown and red wire connects correct?

Then what is the smaller spade connection for? I don't seem to have a wire to connect to that in my loom anywhere.



Because I didn't like the look of this:



I decided to run 2 new separate wires up from the starter solenoid, one to feed the 2 brown wire which carry on towards the bulkhead and one which i've put through a 20amp inline fuse to the relay - Hopefully that'll prevent a repeat of what happened last time:



Then heres the new starter relay wired up with a new plug too:



Then finally this is how the start motor will be wired. Its a bit messy but should work right?

I've got the brown/red going from the large spade to the relay, the standard brown wires off the solenoid and then my 2 new brown wires one to the relay and the other back into the other browns in the loom:



Does this all look ok now?

[mike.]

Bump

[maccers]

The smaller spade connector at the bottom of the starter is for a ballast coil. It provides +12v when the engine is cranking to provide extra power to the ballast coil. When the engine is running that connections stops giving 12volts to the coil, and the pink/white wire provides the constant voltage. Not all cars have this, mine was a ballast and used this connection (yellow/white wire) to the lower connector on the starter, then I fitted a non ballast coil so had no need for it.

Do you have a yellow/white wire around that area?

[lrostoke]

yes that wiring looks ok, no need worry about the small spader at bottom of the solenoid, like mentioned its the ballast byepass wire (yellow/white) you have no dizzy so I assume no standard coil, so not needed.
The wire should be there somewhere you can just tape it up I think 1984 onwards got the ballast system.

[lrostoke]

Hey up

read it again you even copied it I said starter relay not solenoid, about mid 80's onwards theres a relay for the starter circuit before it goes to the solenoid

[mike.]

Speaking of earths, does this look ok for an earth?

Off one of the breather bolts on the transfer case and then to the clutch hose mount on the bulkhead. I'm using a braided hose for the clutch so that bit of the bulkhead was free. I've used washers to bridge the hole and give the cable something to bolt onto:



Its just my dad was questioning this earth mounting earlier...