Lumenition optronic ignition fault finding / wiring

[pooh]

The rebuild of my '86 Xflow continues. I have two querys -probably related.

In re-wiring the lights, I have joined the black wires from the headlights and indicators to the black in the loom -thinking this must be ground(?) When I switched on, something went 'phut' -not a fuse- Doh! Now I can't get a spark out of the Lumenition optronic ignition.

Anyone know of any tests I can do to check the ignition is OK? Also, is that black wire ground or not?

-Going nowhere fast!

[Revin Kevin]

POOH

You can't assume black is ground , get a wiring diagram. As for the lumenition , first make sure you' ve got 12v to the low tension side of the coil . If so with the power on take the cap off and pull the HT lead to coil out of the cap. Place the conductor about 6mm from a safe ground ( hold with something well insulated , 12000v up the arm smarts). Then pass a piece of paper between the optical lenses within the dizzy , you should get a spark at the lead. Try this first otherwise I'll be going on for ever and I'm a slow lazy typist.

 

CHRIS

 

REAL SEVENS HAVE IRON B'LOCKS

Metro power I don't think so.

[pooh]

Chris. Have tried your test -no spark. Also the LED sensor is not lit -I presume I should be able to see light(?) it being optical and all. I have 12V at the coil, but only 7.7V red to black, and 2.3V blue to black at the dizzy conector. I have a recent wiring diagram -but it is very different to my car!!

Whats to check now?

 

[John Hughes]

The black to red voltage in the lead to the dizzy sounds ok that just powers the LED which I believe is infra red so invisible I have previously measured it at about 6v.

 

The blue to black is either off or on and is "switched" by the "chopper" passing through the "beam" this triggers the pulse to the coil to produce a spark

 

regards

John

[Revin Kevin]

POOH

There is four possible faults , from what you've got some sound more likely than others but lets be logical about it. The 4 poss faults are;

1 optical switch

2 Ignition module

3 coil

4 Wiring fault

Firstly test the ignition module by (with the power on) shorting the blue and black wires to the ignition module at the in line plug before the dizzy. This should again give you a spark at the HT lead ( you are replacing the switch)

If still no spark it is probably the ignition module . If it is weak it could be coil , bad earth .

If you do get a spark suspect the switch . TO test this as you put your piece of paper thro the optical switch the voltage on the blue to black leads should change from about 7v to 1v.

To test the coil you need to measure the resistance across the primary and secondary windings. Across the primary it will probably be about 3 to 3.5 ohms ( it can vary dependant on what exact system your using .

Secondaries are harder to measure as it many thousands of ohms. Or the other slightly more dangereous way is to put direct 12v supply on and off primary winding and you should get a sperk at the HT lead.

 

TRY this and let me Know

 

REAL SEVENS HAVE IRON B'LOCKS

CHRIS

[pooh]

Sorry for late reply, could not access the thread. When I short the black / blue or do the paper thang I get a change from 0.6V down to mV's at the brown from the amp to the coil. I'm a bit confused as to how the system works, but I don't think it's going to go as is! I think I must have blown the amp.

[Revin Kevin]

POOH

E mail me direct and I'll talk you thro faulting the system and how it works

 

REAL SEVENS HAVE IRON B'LOCKS

CHRIS

[pooh]

Thanks for your help Chris, but I'm new to this bulletin board lark as well. How do I find your E-mail address?

On the tecky part, I called Lumenition today, they kindly sent me a fault finding guide, which basically confirmed all you guys have said, but also a large warning that if the brown wire to the -ve of the coil should ever see 12V it will blow the Amp. I'm puzzeled though, doesn't it see 12V through the coil? Am sure my amp is blown as I am not getting a 12V to <1V change on covering the IR pick-up, so I've ordered a new unit. I'd like to be sure I understand the system though, so I don't blow the new one as well.