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All switches working fine then nothing at all, although a few weeks before this happened the passenger front did have a hissy fit and went up and down erratically when closing it.
I removed switch panel to try the checks Gilbert’s described, 47 ohms one side with 900 ohms the other, all of them the same. Does that mean I have a small short? but why on all of them?. I have checked continuity between the voltage reg and board socket but no circuit through D1,presumably that's a diode, would a continuity test work?. Will put board back in morning and check for 12v at regulator, cant see any corrosion and no liquid has been spilt on it.
Thanks Richard.

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Theres a microcontroller on the panel which reads all the switch positions and sends them to the BECM over a serial bus connection. If that micro or its supporting circuitry has failed, the whole panel stops working.

Diode should work on a continuity test, but only in one direction, you may need to reverse the meter leads.

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It wasn't me that posted the tests but Marty. Check that you have 12V at the input to the voltage regulator and 5V at the output. I've seen mention of the 5V rail being accidentally shorted to ground which takes out the regulator.

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I got 5v at voltage reg so all seems fine with that where is the microcontroller? I realised after posting that Marty did the post about the switches. When I turned ign on to check for voltage on the switch panel the trip mileage reset to zero, and the courtesy light at the front started working when door is opened, it had not worked for nearly a year. Also the four lights on the suspension switch are all lit when driving and suspension is at normal ride height.
Not forgetting the ongoing problems with the abs etc for over 12months what’s a few more problems, mot in April so if not sorted by then it will be parked up.
Thanks for the input, Richard.

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Fuse 1 supplies a constant 12V to the window switch panel and it also supplies the instruments, so disconnecting that will cause the trip to reset. There doesn't appear to be any connection with the interior lights though but checking for corrosion on fuse 1 pins would be a good place to start.

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That’s why I need help because I overlook the simple things, I removed fuse 1 to check it so that answers the trip mileage reset. I had the trim in the footwells out last year to do the bypass on the multi connectors when looking for the abs fault I can remember cleaning one Earth on passenger side but I will have a check around.
I think I’m getting too old for all these electrical problems and might just go back to a Land Rover built before electronics took us over.
Thanks for the help, Richard.

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Today is a very good day I realised last night that somewhere I had another switch panel, found it this morning and it works. So now to research the EAS problem , I will most likely be back when I need advice.
Thanks again Richard.

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That's good news anyway but they don't normally just die, something must have killed it. What's the EAS problem?

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Now the windows are working I can look at my leisure at trying to fix the old one.
EAS has worked perfectly for the 20 months we have owned it, but last week I had parked with the nsf wheel a few inches inches higher than the other 3 to allow my wife to get in and stop the wind from trying to close the door.
When we drove off all four lights on the suspension panel were on and then slow max speed 35 mph on the dash, no reaction when pressing suspension switch. We drove about 7 miles suspension stayed at running height and is still the same now. Can Nanocom diagnose any problems, I have looked on EAS setting but am unsure.
Thanks Richard.

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All 4 lights means it has detected a fault. With the Nanocom, go into EAS, go to Faults, read what the faults are saying then click on clear faults and come back out of it. That will reset the fault so it should start working normally again. Once you know what caused the fault, then it can be investigated.

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I will go and follow your instructions and report back later.
Thanks Richard.

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When I went in to EAS page no faults shown then the message unable to connect to ECU came up had key in position 2 is that correct?.
Thanks Richard.

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Yes, ignition needs to be on for all systems except the BeCM where it needs to be off. It's usually the HEVAC that puts up a bit of a fight connecting, EAS is usually OK. Make sure the OBD socket isn't corroded. EAS uses pins 11 and 12 which aren't used by any of the other systems.

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Went out last night to look at OBD socket and connections in left hand footwell, connectors by kick panel are perfectly clean as are OBD connection's, whilst there I decided to look under seat at EAS unit connection. Someone has obviously had problems before because the large connector on EAS unit has a broken clip at one end and it was not pushed fully in.
I secured it with a cable tie and that has fixed the problem, no lights on suspension panel and it goes up and down as it should. What a relief, I will try Nanocom to see if that has cured the connection problem. I don’t know why the connection had come loose must have been vibration.
Next job is to change ABS ecu to see if that sorts my very intermittent fault.
Once again thank you Richard.

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The window switchpacks do unfortunately have a tendancy to just fail.

If EVERYTHING stops working, then the fault is usually some of the tiny vias (through PCB connections - the little holes). They are usually plated with copper to connect the circuit through the board, but if there's been moisture etc and they corrode out, then the circuit breaks and it stops working.

Most of the window switchpacks I've repaired, which have just stopped working have had anywhere between 1 and 5 or 6 of these connections broken. The reason the switchpack just stops completely is the ones that fail are usually ones on one of the serial bus lines - so if any of them stop, the whole thing stops.

If you are OK at some tiny soldering, then they are repairable - I used to use a 0.3-0.5mm drill bit in a small rotary tool to drill out the corrosion through the via, and then scrape a bit of the masking off the track, and solder a bit of thin copper wire through the hole to re-make the connection.

Pretty easy fix (but I do have an electronics background) but can be a bit fiddly to find where the break(s) are. I did at one point draw out the circuit diagram for most of the serial lines on the switch packs so I could just probe a number of places to check the common culprits, but I haven't found them yet in all my stuff I sent over when I moved :(

Marty