In reply to a message from cadjag sent Mon 2 Jun 2014:
ok checked voltage to all injectors test light lights up on
all 6 injectors. I did other test with noid on negative side
of coil and ground the noid lights up and flickers on crank
checked all grounds now going to check ECU pin #1 and others
what pin or pins give power to Ecu is Ecu power always or
just when running??
Main power to the ECU is delivered by the main relay to ECU pin #10,
Daniel - ECU is always powered with ign key to ‘on’ or ‘crank’
Perversely, while the noid test coil neg/ground flickering implies that the
ign amp is working - it is not failsafe. Sometimes it seems normal, but is
faulty nontheless - but if you have replaced the amplifier with no change,
there are some odds, but no certainty, that either is working…
Do check the coil connections - this is getting most interesting…
Frank
xj6 85 Sov Europe (UK/NZ)-----Original Message-----
From: sawyer10702
Sent: Tuesday, June 03, 2014 5:29 AM
To: xj@jag-lovers.org
Subject: Re: [xj] 1986 jaguar series 3 xj6 starts but wont stay running
In reply to a message from Frank Andersen sent Tue 3 Jun 2014:
OK the problem on my Jaguar xj6 series III was my coil wire
black?white with white/blue/slate were on the positive side
of coil instead of negative…I only had my haynes manual
page #270 late model series III diagram is labeled wrong its
supose to be early series III wire diagram…I was told that
it is wrong go figure…So a BIG THANKYOU to all you guys
that helped with my Issues…It is so APPRECIATED…So
cheers Lads well done. Now I know how that system works.–
Daniel Sawyer
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
Car will not start I have checked and I have spark the trigger wire is okay as is the earth wires the problem I have is the injector plug has power to both when taken off the injector so the noir light will not blink when cranking have tried 3 icu units but both wires pins have power still pump is okay resister has 12volts I can not work out why both pins have power when taken off the injector and only have power to one pin when they are all disconnected thanks jeff
For firing the ECU grounds one pin.
Check the wire from the coil that runs along the water rail and goes into the fuel injection harness. That gives the impulse for the ECU to fire.
With ignition on you can re-and disconnect the bullet connector in that wire and listen if the injectors click.
**
There should indeed be voltage on both pins on the injector plug with ign ‘on’, Jeff. And with the noid connected between the pins; the lamp should be off…
While cranking; the lamp should indeed flicker. The ECU, when triggered, grounds one injector plug in step with engine rotation, causing current to flow each time - lamp blinking. Does the noid, while cranking, stay off - or fully lit…?
As David implies, lack of trigger pulse from the coil neg is the likely cause. There should be two white/black wires at coil neg - one to the ign amp (which functions properly, as you have ignition), and one white/black to the ECU…
Trace the latter, as David explains - it goes from coil neg via the injector resistor pack and the bullet connector mentioned to the ECU, and test as described (ign ‘on’)…
If the test fails; check continuity between the bullet connector and ECU connector - and then from the bullet connector back to the (disconnected) white/black at the coil neg…