Strange electrical problems?
 

Just back from a week's holiday to find the battery flat, as in dead, not a peep!! Remote unlocking wouldn't work, not even a 'click' from the starter, no lights on dash nothing. Car park gave me a jump start with a battery pack, but......sun roof not working, 'ER' on ATC (which is also really dim and almost unreadable), indicators appear to work but no 'tick' and none of the direction markers on the dash work, hazards work but again no 'tick', and no corresponding lights on dash, no (hi-line) radio/satnav, wont switch on. Have checked some of the fuses for the above a nothing appears to have blown. After putting the sun roof fuse back in, hey presto it started working(?!) However the alarm system wont arm (no red flashing light on dash) and the key fob will only unlock the car not lock it!!:shrug: Looked in the boot well and yes there is some water, but not flooded, so might this be the problem and what's the cure? Should I disconnect battery and leave for 5-10 mins for car to 'reset' itself? Anyone had any or similar problems?

The level in the boot might have been higher at some time. Wait until the light goes off on the satnav CD unit, after leaving car untouched with boot and bonnet open, then disconnect the battery. Unplug both units in the wheel well and after battery has been off for 30 minutes reconnect it. That should sort out the rest of your problems.

Remove the two units from the boot and try leaving them for a few days in a warm dry place, to dry them out before refitting (again with battery disconnected), they might work. Whilst you are waiting for them to dry, remove the rear light cluster lens and check to see if the gaskets are split - if they are reglue the joint edges with superglue. Also check the vents in the sides of the boot, under the bumper sides for possible leaks.

I'll give that a try and post up what happens. Thanks for speedy reply and the advice!!:)

There's been a lot of rain lately. Are you sure that the plenum chamber with the main ECU and the pollen filter is dry? If not then check it first, wet ECU is often the cause of peculiar electrical problems.

JCW

Right here goes....sat nav/radio etc all disconnected in boot well, (towel in to dry up!!), battery terminals off for a couple of hours. Reconnect terminals, all ok and everything working as it should (ex radio of course!!). Short drive, park up for 1 hr or so, come back, problems reappear (no indicator tick/ no heated rear screen etc) and this time engine management light has come on:eek: This now sounds like a big money fix :(. I checked the plenums just before going on hols and all clear, will check again tomorrow. Any more ideas or is this a trip to the ex dealer for an expensive T4 session????

PS Should say it's a diesel.

While you are in the plenum area check on the glow plug relay which is near the ECU. It doesnt like getting wet any more than the ECU and has been known to cause problems when wet.

If you have a fuel burning preheater fitted disconnect it. Also known to cause odd problems when going wrong.

Worth eliminating these as its free to do and may possibly be the cause of you problems.

When the battery is goosed all sorts of electrical gremlins show up, do you have a spare to try out?