Code 42??? What next??

[MattF]

But it will help me.

If the signal from each of the speed sensors goes direct to the ecu, then one goes out to the speedo, then the ECU could flag up a duff speedo sensor. Assuming a broken track in the instrument pod is causing the problem, infers that the speedo sensor data goes via the instrument pod to the ECU - which seems like cr@p design to me.

Do you have a diagram that confirms this on your server? The only ones I've seen are the ECU diagram (just has two speedo sensor I/Ps, doesn't indicate where from) and an overall wiring diagram which doesn't appear to show two speedo I/Ps so is probably a MT ECU...

Judging from the generic speed sensors pdf:

http://forums.bauchan.org/portal/downloads.php?rid=145

the sensors standard design is straight, (exempting the combination meter?), to the ECU, (providing ECM = ECU?). Have you had a look at the last file on page 4?

http://forums.bauchan.org/portal/dow...hp?dcid=14&p=4

Can't remember what that one is, offhand. Judging by the description I added, that could be owt.

[Apache]

You need to just measure from one point to another on PCB track. You should be able to trace where they start and finish by eye, and you should get a resistance reading of 0Ω, or near 0Ω. Check what your meter indicates for open circuit (will probably be something like --.--, or flashing display) and if you see that you have broken track.

Its quite hard to do via the forum!

Cant open that last file Matt. You know me and computers.

[MattF]

Cant open that last file Matt. You know me and computers.

Honestly mate. What are you like. That's a torrent file. I've copied the actual zip across to the webserver though so you can grab it the easy, (numpty), way.

http://outgoing.bauchan.org/tmp/wiring_diagrams.zip


p.s: Let me know if you can think of a useful description for that download.

[Apache]

Nowt there that helps really... though a useful set of diagrams nonetheless. How about 'ancilliaries'

I think what I'm gonna do is connect our portable scope to the speed input on the ECU and go for a drive...

[cara-croft]

Yes..yes.yes..yes..yes..I think Im nearly there !!!!

At last a sign of life in the old clocks yet!!!

After tracing all the PCB tracks and finding nothing wrong, I went back to the plugs and the wires coming from them. Even though I had checked them before I was more convinced it was to do with them.
(I know... as TonyN and some others of you said at the beginning - the wiring!! )

Well, now after pushing the individual wires into the plugs more, I have got a Rev Counter, Petrol Guage, Temperature guage and Handbrake light back!!!
So Everything is back except........... THE SPEEDO!!!!

Lucky enough we live on a farm, so have plenty of safe tracks to drive along, playing with the wires of the plugs so that I can see if the speedo is working, the others I could do stationary just with the engine running ....... I've not fried myself yet!!!

Although I didn't notice it come on, the trip counter has moved fractionally and so has the total mileage. Are these on a seperate wire to the speedometer itself?? Because I'm sure this has never lifted off zero since this problem or did I blink!!

As you know there are white, blue and brown plugs. The white plug is the worse but none of them seem to plug home tightly, is this normal does anyone know??

Are the plugs easy to replace? Can't see how the wires slide in and out??

Wow, just looked back at my post..... sorry us girls don't half talk don't we!!!

Thanks for all your suggestions, even the offer of the clocks, that was really sweet of you, but Im determined to sort this out!!

Bye for now

Cara

[Apache]

If the contacts in the plugs are sha99ed, you could always solder them. Given the amount of effort you've put in, I'm sure its not beyond you.

[MattF]

If the connectors are coming out of the plugs when you plug them into the pcb sockets, you'll probably find you've sprained the retainer lugs on the contacts in the plug. I usually get a little dentistry pick/hook or suchlike in there and splay them back out, or pull each loose connector out of the plug completely, one by one, and splay the lug back out with a knife blade, then push the connector back in until it latches in position. The retainer is usually just a flap of metal on the connector. Don't bend them too far out though, otherwise they'll snap off.

The bodge method would be to make sure all the connectors are firmly pushed into the block and wang a cartload of epoxy resin on the back of the plug to hold them all in place.

[Ava_Banana]

Cara - only just noticed this thread - sorry

....whereabouts are you in relation to Chelmsford.....I am no technical genius, but could possibly help.

[BUSHWHACKER]

My turn.
Cara, you say the problem/s started after you un-plugged/plugged the multiplugs at thr rear of the instrument cluster.
Check the copper strips on the flexy circuit board where they enter the plug sockets. One of more could be broken there as they are pinched and 'stretched' slightly when the multiplugs are inserted.

From memory, I think it's the first or second wire in from the left on the first plug, as you face the clocks that is the power supply wire.

[cara-croft]

Finally all done !!!!


Thanks guys for all your help everything is now working!!!

Thanks to Matt and Andy who have stuck with this thread from the beginning, all your advice etc has been great!!

I did lift the plastic lugs that holds the plugs in and that seemed to make the difference.

Hi Vince, thanks for your tip, I checked the contacts like you said, but they were ok in the end.

I didn't need to resort to epoxy or anything else after all, but you never know if the next bumpy ride will set the clocks off again!!!

Hi to "Mark in the nice part of Essex" I thought only I lived in that bit!!! Thanks for your offer but after several weeks I've done it!!!! Perhaps I will see your truck around, maybe we could swap Surf photos and I could give you and your family a wave if I see you around!!

Cara
A very happy Surfer!!!!

[Apache]

Excellent job!

It seems that the speedo sensor must go to the speedo then the ECU then, as a duff connection at the speedo causes OD light to flash.

Clocks out this weekend for me then!

[cara-croft]

Excellent job!

It seems that the speedo sensor must go to the speedo then the ECU then, as a duff connection at the speedo causes OD light to flash.

Clocks out this weekend for me then!

I hope you manage to sort it, its a nightmare isn't it........

I took out the stop fuse for 10 seconds+ (which I read somewhere, probably never find where it was again!!) and that reset the flashing O/d Light so now I can drive without the infuriating flashing there all the time!!!
At last its a win/win situation!!
But I can't stop checking the clocks when I drive to see if they are still working!! I'm sure it will wear off!

Cara