406oc.co.uk

First of all, thanks to everyone for their help before.

I have splashed out (don't tell the wife) on a Lexia kit and finally, after much faffing with my laptop, got it working and read my cars faults.

The faults are:
1) Intermittent fault. Brake contact signal. Coherence between the 2 brake switches.
2) Accelerator pedal signal 2. Coherence with accelerator pedal signal 1.

Does anyone know how I can go about fixing these? I have already swapped the white & black brake switch over.

Many thanks,
Glen

PS - If anyone wants to use the Lexia kit, let me know.

Glen,

Your earlier post about the brake switch fault makes more sense in the light of this information. Afraid I don't know what it's telling you, other than the implicaton that one brake switch is working and the other is not. Have you checked the fuses - F3 supplies both switches, but it would be worth making sure you actually get +12V at both. (Haynes diagrams aren't very helpful here as they show a cruise control ECU, which I think only petrol cars have - the diesel engine ECU handles the cruise functon). F11& F12 get their supplies via F3, and feed the left & right + hi level stop lights respectively. Do all 3 work? Every time?

Did you try using the online help within PP2000? Usually, if you double-click the fault code or click help at the bottom of the screen, it will suggest possible cause(s) or how to narrow it down further.

I didn't think there was a switch, or switches associated with the accelerator, (other than kickdown on an auto), but you never know....

The above may not be any help, but maybe if you try those suggestions & let us know what you find, we may 'trip over' the answer.....

glennethwest wrote:2) Accelerator pedal signal 2. Coherence with accelerator pedal signal 1.

What this means is the two voltages coming out of the throttle pot don't agree with each other. Usually caused by corroded or dirty tracks inside the TPS which is ludicrously expensive new. This would likely flag the engine management light and triggered limp-home mode while it was in effect. You may not have even noticed it happen though

I suggest taking off your TPS and giving it as good a clean as you can with electrical contact cleaner. Drown it and turn the pot by hand until the cleaner evaporates off. Clear the fault and see if it comes back. If so, try a TPS from a breakers yard


As always with diagnostic tools, I feel the best action is to clear faults without paying much attention to them (make a note of them though). Drive the car to trigger your problem, then look what the faults are now. This eliminates a lot of messing around with red herrings.

I've had another look at things using the Lexia but I don't seem to be able to clear the faults. I can get as far as entering milage but then I recieve:

Erasing Faults - Communications Error.

Any more tips??

Entering mileage? Sounds like you're trying to do an initialisation (more likely than not won't work without brand new parts!) instead of clearing the fault codes... You should be in the 'test by ECU' section then 'engine ecu' then engine type then 'clearing of fault codes'

I've run both the full scan and the engine scan.

I read the codes and then click on the option to clear them.

It says that I have to enter the car's milage which is then stored. When I do this it comes up with Comms error.

I did use the internet update thing on the original software to update to latest version. Could that be the problem?

I am going to un-install and re-install to see if that fixes things.

Oh, school holidays, aren't they great for wasting time...

So I've gone back to the original installation of the software and still the same problem.

I go through ECU etc. and select my engine. I read the faults and the two stated faults are displayed. I then click on F6 to look at the details of each fault and then F1 back to the menu. I then click on the Clear Faults option.

It states that. Before erasing the fault, an after-sales zone must be completed. There are 5 service zones already store of a maximum of 50.

It asks for mileage to put in zone 6. Which I convert to KM. It then confirms the mileage. Then click OK and there is a Communication error.

Help!!!

Glen,

I have been able to clear faults without this problem - normally only get to the 'service zone' bit as I try to exit. Fairly sure I just use a combination of F1's & F7's to get out. Never bother filling in the mileage etc.

It can be a bit confusing as it's not always clear when some actions are complete - often find myself using multiple F1's to go back & re-scan for faults, to ensure they're gone.

Other problem is it's difficult to remember exactly how you did things when not in front of, (the same), computer.