SO finally got most of the wiring installed. Cutoff switch connected, stalk switches connected, everything except warning lights and instruments. So
insulate all the instrument supply wires and try turning it on - crank the engine a couple of times, no problem - turn off, plug last stralk switch
(washer pump) on - try again - engine turns, wiper motor works, then
smoke from under the dash. Somewhere.
Turned everything off, hunted, found nothing. No hot wires, no disconnected earths, no melted plastic bits of insulation, not a thing.
Reconnected the washer wires to correct terminals.
Tried again. No more smoke. NOthing hot, nothing at all to suggest anything.
But something somewhere must be shorting, or carrying too much current. But I have not the faintest idea what, nor how to find out short of trying
again and seeing what happens.
Has a fuse blown? If one has it might give you a clue of where to look.
Geoff
Take all your fuses out, then replace them one at a time. Put in a fuse, turn on ignition, look for smoke. If no smoke appears, take out that fuse, put in another, repeat the test. Keep doing this until smoke appears - at least then you'll know which circuit has the problem!
Fuses all OK.
Just tried again - the earth resistor for the cutout switch, the one which earths the alternator feed when cut off, is getting very hot. But it
shouldn't have current when cutoff switch is ON, and testing with a meter - switch off, live feed to starter/alternator connected to earth as it
should be; switch on, not shorted.
Thinking on run - may have connected cutoff switch incorrectly, so the normally on terminal joins earth resistor to ECU feed, and the off terminal joins ECU input to alternator side.
Fixed.
Had done exactly that, the normally-open alternator earth conected the ecu to nothing and the battery was shorted to earth via the resistor when
master switch on. Which would explain all.
Amazing what you can think about while running, apart from pain
great human mind!
Also great you found it yourself and shared it with us
Thanks. Of course really just very stupid to have connected it that way in the first place, but...
quote:
Thanks. Of course really just very stupid to have connected it that way in the first place, but..
Spent this evening che3cking everything - seems OK, no earth fault anywhere except the starter solenoid cable is earthed - is this correct? Diagram I
have not entirely clear!
Thanks
hmmm,
Not exactly clear what you mean.
The starter is normal connected with "red" to the "+" to the battery, with M8 bolt.
Then there is a small cable which is connected to the "ignition/starter switch" on you steeringcolum.
In the neighbourhood off the starter is normal a "brown" cable connected to the bellhouse/engine which is also connected to the car body, to
make some real good earth.
This prevents 'earth-loss' and shorted earth between different devices
older starters me have an extra connection which leads to the ignition.
This was at the time that there were resitor to gain 9Volts.
greetings
[Edited on 15/8/07 by t.j.]
My starter has
White/red - solenoid supply - to ignition key
Brown - from alternator - supplies loom power and connects to same terminal as
Red - straight to battery
Negative earth so earthed through bellhousing
The altenator has:
B+ which goes to the battery + (could be connected to the + on the starter (normal red-cable)
B- which goes to the engine (normal brown-cable)
D+ goes to the lamp at your dash
quote:
Originally posted by t.j.
The altenator has:
B+ which goes to the battery + (could be connected to the + on the starter (normal red-cable)
B- which goes to the engine (normal brown-cable)
D+ goes to the lamp at your dash
No longer smoking, thanks!
Just have to work out why the light relay bizzes and nothing flashes when I switch the indicators on now, but I'll leave that until all the
lights are connected then try again