Help needed ! Switch unit or coil ???

[workhorse '90 8v]

Hi i'm having trouble tracing a problem in the starting/ignition system.

going by the Haynes manual i believe i've traced it to the starter switch unit or the coil ?

When connecting a voltmeter across the low tension terminals of the coil, removing the hall sender plug, switching on the ignition - i'm supposed to get an initial 2volts dropping to zero..
I'm actually only getting 0.01v

Secondly, when checking the voltage accross the outer terminals of the hall sender plug i'm getting upto 12v , when i'm supposed to only get 5v

Haynes says renew the switch unit and coil.
Anyway of telling which one it is?
Is the coil likely to have failed?

I have had an intermittent problem of the car not starting (starter motor turning over though)
And currently the starter motor will not turn at all.

The starter motor is not at fault - having added a known to be working one from a mates golf.
Also ther does not appear to be any open circuits or dodgy earths.

Any ideas/help much appreciated.. thanx

[workhorse '90 8v]

Though would a failed coil prevent the starter motor turning over?

It's a bit confusing this electrics business

[Blue MK2]

i know might sound silly but is your battery up to cranking standards?

[workhorse '90 8v]

 

[Helios_Blue_Valver]

Though would a failed coil prevent the starter motor turning over?

It's a bit confusing this electrics business

The coil will not keep the car from cranking. I would replace the switch if that is the 2 choices. Not a hard job as it just plugs in. Could have a worn track in the switch that is only making contact sometimes. Get one from a scrappy and try it out.

[workhorse '90 8v]

Yeah i reckon thats the way to go... thanx

[Helios_Blue_Valver]

Yeah i reckon thats the way to go... thanx

Let me know how it works out. Curious on this one. Might be a compilation of problems.

[workhorse '90 8v]

Great news!  Car finally starts!!!!

Various problems in the end.

A - starter motor fcked.
B - TCI-H switch unit bust.
C - possably the imobiliser causing probs..?

The immobiliser came out no problem.  Most wires were tapped so only needed disconecting, infact onlt one wire was chopped so no prob reconnecting..

The local scrappy aint exactly huge, so after not finding the right starter on the shelf, we managed to pull one off of a Seat Toledo of all things!!  As it happens exactly the same Bosch unit, only one electrical plug being different..  And the car was written off at 40k so the starter is in good nick.. Result for 20 bucks!!

Thanx for everyones help.  I've learnt loads.  Can change a starter motor in half hour now, lol !!  
 
 

[Blue MK2]

Nice one

[workhorse '90 8v]

cheers guv  

quite pleased we sorted it without having to take her to the garage..