Odd electrical problem..

[bogbeast]

Slightly odd one this. Wondered if anyone has come across it before.

Go to start car this evening. Stick key in, turn, everything lights up as per usual (alternator light, yellow LED that I still don't know the purpose of..), turn more, engine turns over but doesn't catch.

Puzzled, I stop. Turn key back to off and remove....

... and notice that alternator led (and yellow LED) stays on. Also central locking/alarm is inoperative.

Turn key, engines turns over, still doesn't start & lights stay on

The only way I can get the LEDS to turn off and alarm/locking to work again is to disconnect & reconnect battery. Everything is then fine until I try and start it again

I am thinking sticky relay but am unsure as to which one it could be.

Anyone got a starter for 10 ?

Many TIA

[Fat Griff]

sounds to me, if the starter motor is turning the engine over with no problem, and the alarm/imobilser is not workin as normal, you have a fuelin or possible fuel pump problem. which could be the imobliser failin to disengage to closed circuit on the pump.
listen and if you cant hear the pump wirrr, when you turn the ignition on, thats the problem!!!
then just to solve it!

[BogBeast]

Seems that it was indeed one of the relays in the passengers footwell.

Bosch landrover part.. £25 each

[Northern_Paul]

Any idea which one it was???

Would be good to post the solution..... as I'm sure it will happen to me before long (as I've had about every other 'Odd electrical problem'.

[BogBeast]

'Fraid not. All got a bit confusing, especially as it appears that theres a diode in series with the coil, so testing succesfully depended on which side of the coil you applied +12 to...(took one apart to have a look at.. the one that was actually working.. )

They are both identical, in then end I had both out and tested properly and replaced the one that was duff.. Plugged 'em both back in and bingo..

[Northern_Paul]

If they were loose and not part of the fusebox, and were Bosch metal chappies. They would of been electronic relays and one would of been the 'main engine relay' and the other 'fuel relay' - they both work together (in series) to start the car.

I was just hoping that it was something different, I need to learn more!!!!

[BogBeast]

[quote=Northern_Paul]If they were loose and not part of the fusebox, and were Bosch metal chappies. They would of been electronic relays and one would of been the 'main engine relay' and the other 'fuel relay' - they both work together (in series) to start the car.quote]

Thems the buggers.. Steve Howard (very nice man, always willing to help whenever I ring him) reckoned they are a regular fail..

Intrestingly I still get the yellow and red LED's stay on some times. Theres a big brown relay (iirc) in fuse board (BIG blades on the switched side, auxilary ignition relay I think the manual says), if I pull that out then lights go out. Think that maybe latching, so prolly should change that to...

[Northern_Paul]

BogBeast said:

Intrestingly I still get the yellow and red LED's stay on some times. Theres a big brown relay (iirc) in fuse board (BIG blades on the switched side, auxilary ignition relay I think the manual says), if I pull that out then lights go out. Think that maybe latching, so prolly should change that to...

Yes so do I sometimes, that's why I replied in the hope of gleaning info - it's not a major prob as I will find it eventually - I've noticed that big brown one on the fuse board - I'll look at that if it becomes a pain.

I initially bought these relays from my local TVR dealer and paid about as much as you, last time I bought a pair to troubleshoot I went directly to a Bosch dealer and paid less than £20 for a pair! Used the part number on the top.