75ZT Community

Hi folks have not been posted on here for quite a while - but have looked in very occasionally.

Car a 2004 Facelift Connie SE CDTi Auto.

The car has not been through flood water and the plenums are clear.

One of the front side lights has been out for a while - it is a wiring problem so intending sorting it out when I take the bumper off to install an additional horn so it shows up on the IPK (Instrument pack (IPK from the German)) as a bulb out.

Today went shopping and the warning light went off and came back on a few times and ten stayed on.

Came home and locked the car and a little while later the alarm went off (does not have the sensor inside for movement). Pressed the open and close buttons and was OK for a couple of hours when it went off again. Went out opened all doors and closed them and reset the alarm and as I walked away it went of again so unlocked the car. A little later a neighbour knocked ad told me that the brake lights were on. Went out to check and with the car turned off the IPK was lit up with all the warning symbols showing, mileage etc. Started the car and turned it off. The engine stopped but not as quickly as normal, i.e. turn key engine stops but this time there was a lag. Disconnected the battery and left it for 30 minutes. Went back and reconnected the battery. The headlights flashed and went off, the brake lights were once again on and the IPK lit up. Started and turned off and once again the engine was not too keen to stop. In addition, it seemed to show EP for a split second. With the car turned off the underbonnet pump seemed to be running. Disconnected the battery and put finger to keyboard in the hope that someone can help.

Paul

Hi chaps any help with this would be most welcome.

This morning I have gained physical access to the ECU (Engine Control Unit) (rather than just shining a light in to the plenum to see if it is dry).

The plenum is bone dry and hence the ECU is dry.

Before refitting the covers, wipers etc I reconnected the battery and once again the dash lit up as though the key had been turned. Started the engine and the brake lights went out so drove it round the block and it functioned correctly, the gear indicator showing correctly - R,D,4,3,2. Went back to the house, turned it off and the lights on the dash came on - the ABS (Antilock Braking System) faintly and flickering as the seat belt light (dont think the latter normally shows if a belt is not worn - not too sure of this as belts always worn). Pulling the keys out causes a few changes. Also the underbonnet pump running - not too sure if the in-tank one was.

Took it for a longer run and all was fine. Returned and turned off and the IPK went off, no pump running or brake lights. Pulled key out, put it back in, restarted and then turned off and IPK on, brake lights on and pump running.

Did mention that the bulb out indicator went off a couple of times yesterday. It did not show today until I turned on the lights so it is detecting things.

Any thoughts on problem most welcome.

Supposed to be driving down to SW Wales on Wednesday to help a friend and based on the test drives wondering whether to chance it - he picked up something for me that I bought on eBay that was 10 miles from him, in exchange I have got to go and build a stud wall for him....wondering who is getting the best deal

In addition, the car is a low mileage Connie SE but had body coloured mirror backs and also the steering wheel a little worn so assumed that bits had been taken off to fit on another car. Under the covers, just to the offside of the ECU is a sounder so presume this is a battery back up sounder - what were these fitted for?

As I say any thoughts would be most welcome.

Not something I've ever heard of before
I've messaged someone that may be able to help. Let's see if he comes back to me.

Mick - many thanks.

Will admit I thought ECU but it drives with no problems. Did then wonder ignition switch but could not really think how it could do what it is.

Lates has had a quick butchers at your post. He's at work at present so can't give it his full attention.
Here's what he has replied so far.

Lates wrote: Seems too many things going wrong all at once mate. Try adding a jump lead from battery earth to engine block and battery earth to body. Ping me any results mate. Will ask Peter to read this later

Lates wrote:Also repair the headlamp wiring as at least one fault is there already to complicate things.

Thanks Mick and Lates

Just used the jump leads as stated. Same results as before. Started and turned off several times and on a couple of occasions turning the key to the off position the engine carried on for about 5 seconds until it stopped.

Will see if I can find the wiring problem for the side light but this has been out for quite some time.

It sounds like a backfeed onto ignition, or possibly a loose earth. I might have suggested a sticking relay but can't see one anywhere in the relevant circuits.

Do you have a towbar with a bypass relay? Or any other accessories?

You may also be right with the ignition switch. I'm suspicious that taking the key out changed things, as there's no switch to detect if the key is in or out. Maybe try a little 'percussive maintenance' in the area of the ignition switch next time you see it.

Duncan

Thanks for the reply.

I have fitted a tow bar using the Rover 13 pin wiring kit (I fitted it to my previous 75).

With regard to the ignition switch looking at Rimmers site it appears that the barrel is a separate item. Do you know how he actual switch attaches to the barrel and if the loom from it plugs in fairly near to the column or is it part of a more extensive loom.

Just posted this on FB:
Hi mick, spoke with Pete earlier and scratched heads for a while. The only thing I would think of next is to check the actual ignition switch is powering up/down correctly in conjunction with the key position and retry. This would explain the lazy engine off signals. Next I would be getting the wiring diagrams out to track a common earth for stop lamps and associated circuits.

I have seen separate ignition looms cause weird things on a honda before.worth a punt and checking over.

Many thanks, will check out the switch tomorrow morning.

Thanks for following through on this Lates. Much appreciated.

Has the tow bar been on a while ? Maybe worth isolating this and trying again. Is it wired identically on similar aged cars ? One way if wiring may not be the same on a later vehicle with different fuse board layouts. I Agree with Duncan on the back feed theory. Few ideas in the pot all the same

Hi

The tow bar and wiring has been on for 21 months (wired in accordance with the Rover instructions) and used to tow a caravan and three different trailers.

Think the easiest way of checking the ignition switch is to pop over to Rimmers and buy a new one and fit that.

If that does not work will then check out the tow bar wiring and also check earths etc.

The switch is separate, but the wiring to it is part of the main loom, I'm pretty sure.

I can't remember how the switch fixes on, but I don't remember it being difficult to remove, when I did.

It might be worth disconnecting the Rover bypass relay temporarily, just by unplugging. It could rule out some oddities...

Thanks for that Duncan....

Thought 'if I take the switch off (yes, the wiring plugs in to - have to forget older cars where the wires were soldered to the switch and you then connected in elsewhere) how do I know if it is at fault. Rimmers in Lincoln is not too far so slid over (literally) and bought one. Fits easily, remove the covers, undo two grub screws and off it comes. Put the new one back on and hey presto......same problem. Then thought what happens if I disconnect the plug to the switch and it gives the same problem.

Presume the bypass relay is the one that is part of the tow bar electrics loom (VUB000400) and located at the rear.

Right, just been out and pulled fuse 22 in the passenger fusebox and the car is happy.

So many thanks to both Lates and Duncan (and Lates if I had acted on your early advice about isolating the trailer wiring the cause could have been isolated yesterday).

Duncan is the Trailer Control Unit basically a relay or is it a more sophisticated piece of electronics?

Did use the trailer on Friday and no problem, it was not until we had come back from a shopping trip on Sunday that the problem started. Presume I probably have a chaffed wire unless the TCU has gone wrong.

Also thanks to Mick.

Great result Paul. I'll message Lates and let him know.

The trailer unit is quite complex. However it may be a simple problem, like it's earth has come off.

I can't find fuse 22 on any of my circuit diagrams for 2004 cars. I assume its in the passenger fusebox?