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Posted: Sun Jul 24, 11 8:43 am
by Dave-R
If you measure the resistance between terminals 4 and 5 with an ohm meter you are checking the dizzy pick-up coil. it should be in the range 150-900 ohms.
Disconnect the dizzy lead and connect one ohmmeter lead to a ground and the other to either dizzy connection. Any reading at all there means it has shorted out.
However with the dizzy hooked up again you must have continuity between pin 5 and ground as one side of the dizzy coil has to connect to ground to work. It does this via the casing of the orange box. So if you have no connection between pin 5 and ground it means the orange box is not grounded to the body correctly.
If all this checks out, and you have the correct 8 thou gap on the reluctor in the dizzy, and you still have no spark, then that is the orange box knackered for sure.
Posted: Mon Jul 25, 11 7:02 am
by morgan
All -
I just wanted to say 'thanks' for the time/effort to post on here.
I have taken a day off today with the sole intent of tracing this bananarama! down.
I am armed with the right tools , reference diagrams, and of course the printout of this thread.
Will update later.
Morgan.
Posted: Mon Jul 25, 11 10:31 am
by morgan
Right -
Dave999 - Thanks - All checks out OK ref 12v. Common bar on fuse box running 12ish volts. All fuses check out apart from 1 - (inst) - but then there was no draw on those so its OK. All in all we seem to have 12v.
Dave - Performed all tests. Checks out as follows -
Remove the multi-plug from the orange box unit. When you look at the plug connections refer to the diagram i just posted so you kow which socket in the plug I want you to test.
Turn the ignition ON.
Ground the -ve lead on your voltmeter and connect the +ve lead to #1 terminal on that plug. It is normally a blue/yellow lead going to that terminal. The voltage should be within 1v of battery voltage with everything else in the car turned off. If it isn't you have wiring problems.
Yep - 12ish
Do the same to terminal #2 with the black/yellow wire. Again voltage should be within 1v of battery voltage.
Yep. 12ish.
Now check terminal #3 IF USED. Should be within 1v of battery volts again. Not all set-ups use this terminal though.
N/A
If you measure the resistance between terminals 4 and 5 with an ohm meter you are checking the dizzy pick-up coil. it should be in the range 150-900 ohms.
315
Disconnect the dizzy lead and connect one ohmmeter lead to a ground and the other to either dizzy connection. Any reading at all there means it has shorted out.
No reading. OK.
However with the dizzy hooked up again you must have continuity between pin 5 and ground as one side of the dizzy coil has to connect to ground to work. It does this via the casing of the orange box. So if you have no connection between pin 5 and ground it means the orange box is not grounded to the body correctly.
All fine - strong ground from 5 on box.
If all this checks out, and you have the correct 8 thou gap on the reluctor in the dizzy, and you still have no spark, then that is the orange box knackered for sure.
Well - All checks out. Reluctor gap is a little wide, but the plate it sits on moves about a bit anyway. Has always been thus - have seen it before. Looks like an ECU first port of call. (which should be no surprise I guess
Posted: Mon Jul 25, 11 10:35 am
by Dave-R
Need some imput from other people to see what sort of range these come in. But that seems VERY high to me. Almost open circuit.
I used to have a Mopar I could test to compare with you know?

Posted: Mon Jul 25, 11 10:39 am
by morgan
Dave ignore me - I went back out to try is again. Disconnected coil etc and down to 315ohm.
Connected it all back and still solid at 315. Must have been me but stable now. Please see corrected post !
Posted: Mon Jul 25, 11 10:45 am
by Dave-R
It's looking like the ECU has indeed gone again. Very strange they keep going on you. They are not getting too hot are they?
Posted: Mon Jul 25, 11 10:54 am
by morgan
Its possible - bulkhead mount is over the top of the headers (but then isnt everything under there really ? )
I could try and move it to the inner wing I suppose - optiuons are limited really...
Trying to track one down now without driving hundreds of miles. Will be sure to keep posted.
Posted: Mon Jul 25, 11 11:34 am
by Dave-R
If you look at the way I mounted mine, I made an ally plate to help keep the thing cooler from header heat. I can't remember opening up the cowl behind it so cool air in the cowl would cool it. I know I did consider that but I think I chickened out of cutting open the cowl on a numbers matching 440.
http://www.moparuk.com/forums/viewtopic ... 313#395313
Posted: Mon Jul 25, 11 11:57 am
by Adrian Worman
The ballast will get very hot and that may transfer a bit of heat, but one thing I've noticed is that you don't have a stand off plate under the e.c.u to help transfer heat. I've always had one and I've heard people say that its important.
Posted: Mon Jul 25, 11 1:22 pm
by ANTON
Morgan
I have two spare ECUs if you need to borrow one and if you bring yours with I can try it on my car.
I have a blue and orange ECU spare.
Anton
Posted: Mon Jul 25, 11 4:51 pm
by morgan
Thanks Anton - thats very kind. WIll let you know...
Well folks - 2.5hr drive to Hausners, and I have a new orange box.
Got to make up a couple of connectors but this evening after bathtime and storytime I should be able to try... Fingers x'd
Posted: Mon Jul 25, 11 5:05 pm
by AllKiller
Good luck, and yeah stand off plate/heat sync

Posted: Mon Jul 25, 11 5:16 pm
by Dave999
and earth it well
Dave
Posted: Mon Jul 25, 11 7:47 pm
by Scooby
Morgan always had my ecu where your is located no probs there, just wondering on the bigger picture all this appears to have happened since you've changed over the engines...just thinking or you should what has changed since the swop over...
Hang in there mate these mopars will try your patience to the limit...
Rich...
Posted: Mon Jul 25, 11 8:10 pm
by morgan