thebiglad
Well-Known Member
I would say that they made you a very fair offer there. No problem fix - no pay.
Just hope it's long-term fixed. These issues have a nasty habit of returning.
Cheers
Dave
I would say that they made you a very fair offer there. No problem fix - no pay.
Just hope it's long-term fixed. These issues have a nasty habit of returning.
Cheers
Dave
eightinavee
Well-Known Member
You can usually tell if its loom or switch from live data.If you move the shifter rapidly back and forth the display will flash an "Invalid" reading between actual positions if the switch is dying.If it only shows PRND321 no matter what you do with it then its usually the loom rubbing on top of the transfer box.But then I've seen the EAT ecu give similar symptoms whilst failing.
sierrafery
Well-Known Member
thebiglad
Well-Known Member
You don't say but I'm assuming yours is a manual gearbox car? In that case you need to connect a diagnostic kit to the car to tell the BCU that you have a manual gearbox.
malcolm jones
Member
Hi I was wondering I got the same issue and did the same bought a new switch and still the same did they sort yours out and what was the problem
biketeacherdave
Well-Known Member
You are asking a question from a 7 year old post...doh
thebiglad
Well-Known Member
Hi Malcolm I'm assuming that you're talking about the M & S lights flashing ? This can be caused by a number of things :
1. Lack on volts on start-up. If there is any weakness in the battery and if the driver turns the key straight to engine start (rather than leaving the key at pos. II for a couple of seconds to allow the transmission ECU to do it's test) then this will have a tendency to rob volts to the electronics and they throw their toys out the pram.
The way to avoid this is to ENSURE the battery is good and fully charged, or if there's any doubt replace. Once the battery is out of the way try turning the keys in a step by step way to allow the the ECU's to do their thing before starting the engine.
2. There is an electrical connector between the switch and the car loom. The loom side of the connector is prone to corrosion so needs thorough cleaning with 'switch cleaner'. Access to the connector is - as I found recently on a 2004 car - not easy.
3. Installing the new switch requires careful setting up, otherwise the fault will not be resolved.
malcolm jones
Member
Hi I've replaced the xyz switch but when I plug in the hawk eye total it says there is a Perminant fault on the selector switch I know that. You got to be care ful setting them up but if it started it can't be that far out.also I have no selector lights on dash or gear selector lever do you have to set them up in nuetral and have some one sit in car and move it until n lights up
thebiglad
Well-Known Member
Using your Hawkeye you should be able to set the switch up so that it operates correctly. With the hawkeye connected and selecting the transmission ECU (EATS), get an assistant to select each position in turn and see what Hawkeye shows. Re-position the switch until the results on Hawkeye show the correct positions.
malcolm jones
Member
Don't know if the new total does to be honest I rang the developer who told me that the new machine as a few things missing off the old unit so got to wait for an upgrade but even if was set up wrong on box I should have the lights each side of gear-lever and on the clocks
thebiglad
Well-Known Member
I'm not sure if you're right tbh, if the switch to ECU relationship is not re-established, the EATS will not send the signals to the BCU to illuminate the gear lever lights and dashboard indicator.
malcolm jones
Member
Hi I checked again the switch and tried to alter back and for with someone in cab but nothing the other strange thing is it will start in any gear selector when you plug in the hawk eye it shows it's stuck in 4 th gear and the value on the selector is showing 0000 also showing the voltage when not running at 12.44 and running at 14.33
sierrafery
Well-Known Member
The voltages are OK that way, as @thebiglad said, the signals from the switch dont reach theyr destination so if you are 100% sure the switch is good you have to follow the wiring
malcolm jones
Member
Yep switch is brand new I've got an auto electricians number as I hate car electrics and don't no have much clue give me any mechanics lol so might give him a ring unless it's a gearbox issue with hats causing all this grief
sierrafery
Well-Known Member
The gearbox would not cause such thing to mix up the switch's inputs
malcolm jones
Member
Need some one like you to take a look lol
ROY SIMPSON
Active Member
I had a problem like you and eventually traced it to a fault in the bcu which intermittently was failing to supply power to the wxyz circuits in the switch.
To check this, With the ignition at position 2, test for 12 volts at pin 8 in CO675 , this is the connection of the xyz switch to the wiring harness a picture of which you will find in the electrical library.
If you don't have a copy of electrical library, on my xyz switch pin three bottom right is missing ( as it is unused) and the pins are numbered left to right so with pin 3 bottom right missing, pin 8 is top left.
The colour of the wire to socket 8 in the harness connector you need to check is NP (brown/purple).
Failure of this power input may explain why you cannot synchronise your switch and why you have no selector lights or digital gear position display.
If this is the case there is a wiring fix you can do to bypass the bcu.
To check this, With the ignition at position 2, test for 12 volts at pin 8 in CO675 , this is the connection of the xyz switch to the wiring harness a picture of which you will find in the electrical library.
If you don't have a copy of electrical library, on my xyz switch pin three bottom right is missing ( as it is unused) and the pins are numbered left to right so with pin 3 bottom right missing, pin 8 is top left.
The colour of the wire to socket 8 in the harness connector you need to check is NP (brown/purple).
Failure of this power input may explain why you cannot synchronise your switch and why you have no selector lights or digital gear position display.
If this is the case there is a wiring fix you can do to bypass the bcu.
ROY SIMPSON
Active Member
If you want to read my tale of woe look back a few posts in this forum as someone has resurrected my original post about my problem.
malcolm jones
Member
What is the wiring fix to bypass bcc and where is the bcc located
