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MG ZR ZS ZT Technical - Electrical gremlins

My ZT-T CDTi failed to start today - just after I said it had never let me down in 55,000 miles!!! (I know - I shouldn't have said that!) It appears to have a major short somewhere as the ignition lights come on but computer display doesn't and the starter won't work. Also when you turn the key to start one headlight comes on and the CD auto changer goes berserk!!! The last few days the sat nav display has taken a while to come on (about 1 min)so I thought something was going to happen, although once on it has been working fine.

Anybody had this before or know of a magic fix - faulty connector block somewhere etc?? I have checked all the fuses and poked the relays etc.

Any advice gratefully received!!

G Calvert

OK short term panic over!! I checked the battery voltage and it was down to 10. With the TF attached via jump leads it took 2 or 3 mins and then all the electrics came back - car started so good news. Looks like the battery has been going down hill for a while so I'll buy another - but check for voltage leakage just in case.

Faith in the beast restored!! Here's to another 55,000 miles!!

G Calvert

Strange your battery has gone, mine is original at 4yrs and 80k miles, but then again I should keep my mouth shut and not tempt fate. I did begin to wonder reading your first post whether your ECU had gone down, apparently you need to keep the drains clear otherwise water can collect and spill over into the ECU housing and cause havoc.
Martin ZT

Thanks for the comments Martin, and long live your battery. I fitted a new one today as the old one definitely wouldn't re-charge and the car is back as it was. Amazing what the effects of a low voltage had on all it's systems - anyway I'll know what to expect if my sat nav display fails to come on instantly next time!
G Calvert

Martin, I note your comment about drains. I found the two drains at the top of the engine bay, left and right (in front of the wind screen) blocked and lovely ponds of water gathered there (ZT-T). I cleared the rubber drain tubes out of muck, however after I've washed the car, or it has been in the rain, I swear I can hear water sloshing around somewhere ahead of the driver's seat. This is apparent when I reverse the car, for example when backing out of a driveway, and then stop. Do you know of any other drain tubes or holes to keep clean, or could this be water in the heater or a/c or something similar?


kew if you remove the windscreen scuttle panel on the passenger side you will see a solid plastic panel under it remove the plastic phillips screw and the bonnet seal rubber and gently pull the whole panel forward this will release the pins from below the screen allowing the panel to be lifted upwards remove the solid plastic panel and voila you are into the plenum where the ecu and pollen filter is kept this plenum will probably be filled with water and your pollen filter should be showing a high tide mark.
at the very bottom of the plenum is a rubber drain tube which gets blocked with debris poke a screwdriver or a suitable blunt object through this tube and watch the water flow away these tubes should be cleaned out on every service.

regards andy

This thread was discussed between 17/04/2006 and 18/04/2006

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