Hi,
Ignition bloody woes...
Put it this way, if I can't sort this out, I'm gonna sell my nearly completed Avon - any offers?
Anyway,
Having major problems with a lightning size spark from the HT terminal on the coil to either of the other two terminals (when the king lead is removed). This only happens when the ignition is on and I put the lights on dipped beam or flash main beam. I have the Bosch induction dizzy and black box which I know is all wired up correctly as the car runs fine.
Any ideas anyone?
Graham has suggested the interference due to there being no relay for the lights (Tiger 6 fuse loom) and the amount of current going through the sierra stalks. I just hope I don't have to start pulling the loom apart.
Any ideas anyone?
Cheers,
Pat...

Just to add to the confusion and report on further findings:
When the king lead is removed and I turn the engine over, quick sparks out of the HT socket on the coil everywhere like it's supposed to. If I remove the wire for the tacho (currently connected to the coil -ve) that goes to the dash board (not connected to anything) and then turn the engine over - no sparks from the coil.
The tacho wire is definately not earthing on anything and carries no voltage when disconnected or when the engine is turning over.
Any ideas??????
Pat...

[Edited on 25/4/04 by Avoneer]

id start be relaying the lights, thats surely a good start anyway and quite easy to do if the loom is colour coded, quite easy if it isnt.

are the leads new and good? and do you mean it only sparks with the king lead off?

..You need to work out how a 12+ or, depending on how your motor is wired,a 12v - feed is getting to the coil.Is it via the ECU(the lights are faking a sensor input?)and so on.Don't sell it(Unless it's to me stupid cheap)it'll come right and then something else will happen......The coil gaining a "remote" feed,even if it is a "Fake" from the ECU is/appears to be the problem.A meter on the Lt side of the coil and work back.Write down stuff as you go.Put the meter on.Do the lights,note the reading and so on.Finally you will find the point where the lights are crossing over(Dissconnecting one wire at a time as you go)...Be lucky.With regard to Grahams point bout the relay,it is possible because the relay is providing the isolation between the circuits.

The leads are new and good and it will spark with the king lead off and on - as long as the wire for the tacho is connected (which is just a wire that doesn't connect to anything under the dash yet). Strange.
Thought about relaying the lights. Complicated for me though and hard as the loom is very firmly tucked away under the bodywork.
Pat....

any chance of a photo of the coil and black box you have? cos if its the same as mine (the black box has 6 wires) then i might be able to help. or what engine and age donor is it?

looking at the piccy in the manual, mine looks like the bosch one too.

Hi Joel,
Mine is the 6 wire little black box as well, but there are three variants. It must be wired up right or the engine wouldn't run at all so I don't think the problem is there.
I have a 2ltr Pinto - 1987.
Might be auto electrician time.
May be something to do with how I have wired the lights up to the Sierra stalks. I just don't know......
Pat...

Some things are just too wierd...........

Just to clarify:The feed from the coil to the tacho is just that.It feeds the tacho with negative pulses which are then coverted in a reading(You will notice that tachos are rated for a number of cylinders4,6 and 8 etc,I.e the pulses are more or less depending where you are with the number of pots firing).Now my thinking says to me that some how a trigger is finding its way down from the tacho to the ve- side of the coil(assuming there is a constant ve+ igntion feed on the other side) hence charging the coil......Fault within the dash?Blue h/b warning crossing?Dash back lighting sqifffy?....To add.Remember the coil is fired by a negative signal.The h.t spark will jump to any ground it can.If it gets to the ve+ it is just going back via the battery to ground.

[Edited on 25/4/04 by TPG]

Cheers.
Will go as your first post and check each wire etc and see what happens.
Watch this space.
Must wait for the blood stream to detox the wine though!
Pat...

The black wire to the module is the most likely culprit as it is the switched live. Check what else it is connected to and put it on its own ignition controlled feed.

Just to clarify,
When the ignition switched live goes +ve on the +ve side of the coil, should the -ve side of the coil also go to +ve until it is earthed by the module?
Cheers

Hi Pete,
I connected it directly to the battery and was still getting the same "lightning strikes".
I am going to check everything with my multimeter now and will report back shortly.
Pat...

Right, can't get any sparks full stop out of the coil now.
And when the black wire is a +12v on the +ve coil terminal, the -ve terminal of the coil is now at bugger all - shouldn't it go to +12v?
Think I have buggered my second coil. This is getting expensive.
I also noticed that the +12v ignition wire connected to the +ve side of the coil dropped from 12.88 to 11.50 volts when the lights are on. Is this normal?
Pat...

[Edited on 25/4/04 by Avoneer]

I THINK I' VE BLOODY SOVED IT.............
What would happen with an inductive dizzy if the two wires to connect to the amp were the wrong way round?
Pat...

quote:

---

Originally posted by Avoneer
I also noticed that the +12v ignition wire connected to the +ve side of the coil dropped from 12.88 to 11.50 volts when the lights are on. Is this normal?
Pat...

---

Cheers,
It will probably be something simple like that and something stupid I have done.
Good fun sticking it all on here though. Gives you a good break from the car...
Pat....

Just to be sure sure......Attached drawing.I think you are getting a odd neg to the neg side.

Tried the heavy wire from coil mount to battery - still no joy.
I think a new loom is on the cards as I was never happy with the tiger one anyway. That or an auto-electrician which could end up costing the same!
Any words of wisdom anyone?
Pat...

Pat

premier wiring looms

best £100 i spent on the whole car

all the relay and fuse holders are wired in already and its just a case of plug and play once you have worked out which column stalks you have(83BG or 87BG)
in fact if you ask premier wiring they will sort this for you and even wire up your stalks for a tenner.

i would suggest having a go at doing a loom from scratch yourself. it really is a lot easier than it sounds, and at worst you will fail but learn something! i suspect that your patience is running out though, so maybe it is worth a call to premier or whoever.

i would have a little word to whoever made your original loom though, try for help or refund, and failing that try taking it apart to get an understanding of the damn thing.

i bet it will turn out to be something simple like a missing earth from engine/module/coil etc though.

where in yorkshire are you?

Hi Joel.
I'm in Dewsbury.
Going the premier route I think.
Was never happy with Tigers loom anyway.
Pat...

Just a comment: Never run a coil without a proper spark gap. Doing so puts both the coil insulation and the ignition amplifier under a huge load, and either or both will eventualy fail.

Allowing the spark to ground to the -ve LT connection is even worse.

[Edited on 30/4/04 by MikeRJ]