Ignition switch problem?

[oldgitdave]

Hi folks,

Drove Dusty home from work today & parked her up on the grass verge. Went out to move her into the garage (yes I have space for a car ), turned the key; nothing . All dash lights ok but no cranking. Thought maybe starter motor (had this before with my Celebration) so tried again. Next thing lots of smoke & burning from behind the steering wheel . Sh*t, I thought she was going to catch fire . Switched off quick & the smoke died down. Got the wife to help push her into the garage & have disconnected the battery. Guess there's a short on the ignition switch somewhere but electrical stuff is well outside my area. Shes a 1995 ES so has an airbag (may need to remove the steering wheel?) Are the ignition switches readily available & if so what sort of job is it? Any advise greatly appreciated.

Regards,
Dave

[glasgowjim]

Check the switch first as you dont have to touch the airbag to remove cowling (I have done so numerous times on late model 480's)

A if it is the ignition switch thats faulty then just remove the cowling it can be done without removing the steering wheel then remove the little circular switch on left hand side (remember the grubb screw) put car in neutral and just turn the switch your car should start if its the key lock at fault but I doubt it. if the switch is at fault it should show signs of burning just disconnect and hot wire the car.

Although this is for a non air bag car it gives you an idea of what is needed.

http://www.volvo-480-europe.org/forum/v ... 24&t=18370

B To remove the airbag firstly disconnect the battery for 30 mins before doing any thing about the airbag. This ensures that you are perfectly safe from any accidental activation

That done you can remove the air bag by turning the steering wheel to one side and inserting an allen key into the hole at the back of the steering wheel and loosening the screw it wont fall out by the way. repeat for the other side now remove air bag carefully and slowly as it is connected to the car electrically by a short wire connector.Now disconnect the wire and totallt remove the airbag.

[oldgitdave]

Thanks guru Jim .

It'll be Sunday at the earliest before I can look at this. Hopefully it will be obvious once the cowling is off. I'll report back as soon as I can. Obviously I want a permanent fix rather than hot wiring but at least that'll confirm where the problem lies.

Cheers,
Dave

[glasgowjim]

Also if I remeber correctly the wiring wrapped in YELLOW insulating tape is the airbag wiring.

[oldgitdave]

Got up early this morning to investigate. Finally managed to get the cowling off without removing the steering wheel. Found that the white & blue wire is badly burnt. Hope this photo works, it's the first time I've tried it



Anyway I disconnected & removed the actual switch & I've looked inside it and it all looks OK. There doesn't seem to be an obvious short circuit anywhere. So I reconnected the wiring & the battery & tried to start her using a screwdriver. No cranking at all & got smoke from the same wire. I don't suppose I should have expected anything else really. I don't know how to try hot wiring, whether it would help or not I don't know? So at the moment I'm stumped Any ideas where to go from here?

Dave

[doingitsideways]

Chances are, the red is permanent live and the burnt wire is the feed to the starter solenoid.

To test, just snip the wires (leaving enough to reconnect afterward) and connect the two together before the switch. The starter should then run.

If it was me, I'd be suspecting the starter solenoid at fault.

[glasgowjim]

Steve thats sounds right the starter motor/solenoid can sink a lot of juice.

I should have some spare loom lying around must see if I can find it.

[oldgitdave]

Thanks Steve, Jim,

I was thinking maybe it's a solenoid problem as you say.

Replacing the loom wow that sounds like a horrendous job! Will the wire be burnt along its entire length then, or just the bit up near the switch? I only saw smoke from near the switch. I was hoping just to reinsulate after removing a bit more of the blue tape.

I'm away from home at the moment but I might have a spare starter that I could get refurbished. The solenoid is part of the starter if I remember correctly? The next problem is getting the car high enough to get underneath to do the change over - can't start it so can't get it on the ramps

I'll let you know how I get on.

Cheers,
Dave

[eye of ra]

Try selecting anything other than Park or Neutral and then try and start the car if you no longer get smoke that will eliminate most of the starter circuit and point almost certainly to the starter/solenoid. If it still smokes your problem is elsewhere.

The wire will be melted to some degree inside all the way along. The smoke only came from where it melted to the surface.

[glasgowjim]

oldgitdave are you near glasgow?

[oldgitdave]

oldgitdave are you near glasgow?

Miles away Jim, I'm near Derby.

Tried what "eye of ra" suggested & it doesn't burn when not in neutral or park, so looking even more like solenoid. Thanks for that.

I've peeled the blue insulating tape back as far as I can & there's what looks to be a splice from one wire to two of the same colour (white with blue stripe). Very difficult to see but the two wires don't seem burnt. I guess they've shared the overload? I reckon I could do a repair from the splice.



Couldn't find an old starter motor so must have got rid when I sold my Celebration. Will probably buy a new one on fleabay but there are so many that seem to be compatible but have different ratings 0.85kw to 1.4kw. Obviously the smaller rated ones are cheaper & I suppose will put less load on the damaged wiring. Any idea which one I need or doesn't it matter?

Dave

[doingitsideways]

As for swapping it out, I'm pretty sure I've done one from above before now on a non turbo car.

[oldgitdave]

Well I'll have another look. I'm not as bendy as I used to be . Does the exhaust manifold need to removed?

[doingitsideways]

I don't think so.

Was a while ago, mind.
I'd definitely remember if I had to remove the manifold though, right pig of a job, that!

[eye of ra]

Where it splits one wire will be undamaged as it goes to the ECU and is not shorting out (as proved by no smoke when not in P or N) the other one goes to the solenoid of the starter (via the switch on autos) and will be damaged to some extent all the way along it.

The size of the starter motor won’t realy matter as the burnt wire only goes to the solenoid to trigger the starter motor the main current goes through a different wire that is much thicker.

[oldgitdave]

OK, I've finally managed to get the old starter off from the top. Pretty sure its the original. The worst bit was getting the heat shield off, what a pig of a job . Anyhoo, the small wire going to the solenoid isn't the same colour as the burnt one from the ignition switch, it's a slightly heavier gauge and shows no sign of burning. I wonder if the heavier gauge wire comes from the auto transmission inhibitor switch & isn't burnt simply because it's thicker? Otherwise the problem might be elsewhere .

Unfortunately the new starter has a spade connector for the small wire & the old one had a post connection so I'll have to change that tomorrow before trying to get everything back together. Must say I'm not that confident the solenoid is the problem given what I've just described. Guess I'll soon find out!

[oldgitdave]

Well everything is back together and guess what?.......It's exactly the bloody same . Obviously the white/blue wire is earthing out somewhere else. The auto box inhibitor switch is working correctly, I've proved that. Other than trying to get it to an auto electrician (££££££ ouch!) I'm stumped. It might be a while before I can get this sorted

[glasgowjim]

Okay I havent worked on an auto so but....

From what you said the problem starts when you hold the key at 3 position to engage starter.

When I had an ignition fault with one of my daughters 480's I solved it by hotwiring the ignition just put the ignition on (pos 2) and connected the solenoid to the battery and the car started. Having done that I just put a push to make switch under the dash to start car.

Do a search for " stone age technology " on here for more details

[eye of ra]

Looking at the latest diagram I have (dated 1991, so might not cover 1995) my money would be on the CEM. Disconnect it, put the car in P or N if you don’t get smoke you need a new CEM if it still smokes it’s in the wiring between the auto switch and the CEM.

[oldgitdave]

I'd had some thoughts the CEM might be the issue following on from today's dismal failure, but as I'd just parked her up when the starting problem happened with no running issues whatsoever I'd thought it couldn't be that. I do have a CEM3 spare so will look at the wiring to that to see if there's a smoking gun, looking particularly for a white wire with a blue trace. It's left of the passenger side footwell, right? (UK car).

Failing anything found I will try Jims starting advice in the morning and see what happens.

Thanks for your all your help guys

Cheers,
Dave