Replacement Ignition Module does not work

XJ
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Car in question is a 1988 Canadian XJ12 VIN 480065. The original ignition module was failing after heating up. I purchased a Delco D1906 module and when installed the car would not start. I subsequently purchased a new amplifier (DAC4104) from SNG Barratt, and when installed, again the car would not start. Interestingly, when the old ignition module was installed the car started up normally. The module that works has the ground connection and the D1906 does not. I am obviously missing something. Could I have an ignition system that is not compatible with the D1906 module? Is there some way I can get the D1906 part to work in my system?
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That’s odd, JFR - the AB14 is a complete ‘plug and play’ unit. Requiring only the white wire connected to the coil pos and the white/black to coil neg - and of course the plug to the distributor. Internally; there is a connection to a capacitor and ‘ground’ through a Zener diode.

However, the AB14 requires a good ground through the mounting bolts - and a separate ground to the mountings, as shown on your ‘old’ GM, is sometimes there to enhance this ground - but it is not really necessary…

You may, very unlikely, have a dud from Barratt - or the ‘non-start’ is caused by other factors. Verifying the correct wiring to the coil, and checking the resistance through the pick-up coil is routine. Verifying proper sparking using a spare spark plug during ‘non-start’ may clarify things…?

The module itself is a standard one, from various manufacturers, widely used - though the GM version is highly regarded…:slight_smile:

Frank
xj6 85 Sov Europe (UK/NZ)
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That’s where I’d focus at the moment.

There’s a similar thread running in the XJS section, by the way

Cheers
DD

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Huh ? I may have ignition issues of my own in an entirely different system !!

  1. Lookin at the picture I think I see a ground path.
    The top bolt hole seems to have a tab for that purpose.

  2. I’ve never tried it. so caveat. It can be tested in the car. the module performs a similar function to that of points in the old system of making and breaking the ground path to induce the HT current for the spark plugs via the coil.

In olden days we used a light ins series between the distributor and coil to check operation and even do the static timing of the engine.

Crank and the test light should blink as the points opened and closed.

So, in my theory the same thing should occur with the module.

Carl

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Thanks for the replies. It seem the amplifier I have in place is not the issue. The old style module works and the car starts. The D1906 module mounted in the same amplifier does not. Perhaps the D1906 module is not properly grounded in the amplifier body. I will try an addition ground on the D1906. I really cannot explain what happened with the AB14. As Frank has stated it is a plug and play item. I returned the AB14 that did not work and SNG Barrett is sending a replacement.