I garaged my car for about a week and when I came back it will not start.
After diagnosing a "NO SPARK" condition, I narrowed it down to a failed module (Ignition Amplifier #990 7J60FZ). The interchange part # for this is GM 1875990 or GM 10482820.
Since I had a couple of GM HEI Distributors laying around, I swapped out the module for one which came out of a brand new distributor I recently purchased for my Chevy V8 engine and the car started but would die after about 30 seconds.
I replaced that module for one that I had from an older distributor and the car runs great.

However, I am concerned that the wiring from the amplifier to the coil is incorrect and I believe this is what destroyed the module (amplifier).
Here is what my wiring looks like. This is the way I got the car:

Coil Negative Terminal - 3 wires: White/Black Spiral;White/Blue Spiral; and White from Amplifier.

Coil Positive Terminal - 2 wires: White; and White/Black from Amplifier.

I do not want to run the car until someone can enlighten me as to what the correct wiring connections to the coil should be.

I think I read somewhere that the 2 white wires should be on the positive terminal of the coil and the 3 white/black,white/black and white/blue should be on the negative terminal of the coil.
Please correct me if I am wrong. I do not want to destroy another module.

 

Sanchez,.. I do not have my original wiring anymore so can not help you there. However do you have the S57 publication?

If not, I can send you a copy as a PDF

Lemme know ....

 

I have the S57 but it does not show the engine compartment ignition system wiring. Will look at it again.

 

I know this because I just had to repair and replace wiring harnesses over the last couple weeks.

The + terminal on the coil gets solid white wires, and the - terminal gets white with various color stripes. In this one instance, they make it easy to figure out.

The Jaguar Factory Shop Manual shows it on Figure 96, page 86-25 (13: Electrical).

The S-57 electrical book doesn't include the Amplifier anywhere. Or if it does, I haven't been able to find it.

 

If I put the 2 solid white wires on the positive terminal of the coil and the 3 white with the various spiral colors on the negative terminal of the coil, I have no spark.
However, If I connect as follows , I have spark:
Coil Negative Terminal - 3 wires: White/Black Spiral;White/Blue Spiral; and White from Amplifier.
Coil Positive Terminal - 2 wires: White; and White/Black from Amplifier.

When I opened the amplifier, it was wired like this on the module.
Terminal B: White/Black spiral and ground wire.
Terminal C: White and white wire from condenser.
The White/Black Spiral and the solid White wires leave the Amp and go to the coil
Terminal W & G go to the distributor.

 

Hmmmm.

I can't explain it.

What James mentioned is correct...all solid white wires go to the "+" post.

This will take some mulling

Cheers
DD

 

Somewhat the hard way, like I usually do, I learned that
white is hot from the ignition switch.


So, it seems that whiter to coil + is logical.


So, is it the other colored wires for coil - and the distributor that
is the issue?


If S57 is unclear on this point, perhaps A GM Schematic might
clarify. In each case, the module Is "amplifying" a signal created by the distributor.


At times, thinking out, or as Doug says, mulling needed.
Carl

 

As it is currently wired, the white wire from the ignition switch is on the positive side of the coil.
The white wire from the Amplifier, if placed on the positive side of the coil, and the white/black wire on the Negative side of the coil is resulting in a 'no spark' condition.
If I reverse the two wires from the Amplifier to the Coil I have spark.
Weird but true.
Is it possible that the PO reversed the wiring at the Module? that the White/black wire should go to Terminal C and the white wire to Terminal B????
Does anyone want to volunteer opening an ignition amp and verifying the connections to the module?
As per the GM schematic,
Brown wire on Terminal C of the module goes to Negative side of the coil
Orange wire on Terminal B of the module goes to B+ on the coil.
If I am not mistaken, the Orange wire gets switched power from the BAT terminal on the cap of the GM HEI distributor. Black wire is ground.

Brown wire = White/black wire (Module Terminal C) to - coil
Orange wire = White wire (Module Terminal B)to + coil
My connections are reversed.
Switch the wiring and it will match the above. Will that destroy the module?
I took a picture of the connections before I disconnected the module.

 

I just looked at mine in the car. Three wires from distributor to amplifier. They're taped up so I don't know what the colors are. One has a ring and is under a bolt for ground. The other two go right into the amplifier box. The connectors are different sizes so there's no unintentionally reversing them.

Out of the box are two wires--one white, one white with black stripe, which go to the coil.

I had a second amplifier and it's here somewhere, but of course when I'm looking for it, I can't find it. I may be possible that P.O. opened it up and replaced the module (I did that--it's why I have a second amplifier) and swapped the wires. If I find the spare amp, I'll open it up and see how easy/likely that could be. (The one that's in the car I don't want to mess with ...)

 

Found it. Never throw anything away.

Four photos attached.

1. Front has the label to make sure we're talking about the same thing.

2. Front side shows the two connectors from the distributor (third wire goes under one of the bolts as chassis ground.

3 and 4. Two views with the back off. The back plate comes off with four little screws in the corners.

The rectangle with the SELECT label is the GM module. There are four wires that plug into it. Two are internal and two are external (white and white/black stripe). It would be easy to reverse those two. Not saying that's what happened in your case, but it seems possible to me.

 

Thank you James. A picture is worth a thousand words.
It would seem that the module was initially wired incorrectly.
Looking at James' pictures, it shows that the white/black wire is connected to terminal C on the module and goes to the negative side of the coil.
The attached GM module schematic also shows that the connection from Terminal C goes to the Negative side of the coil.
I am going to reverse the wiring on mine to see the results.
My amp has a ground inside that goes to Terminal B.
There are 2 trigger wires from the distributor that plug into the amp. No 3rd wire to ground as in your case.
Will post results later today.

 

I wired up the amp module as per James' photo and the GM schematic and now the wiring to the coil is as it should be.
Thank you all for your input.
Now, I am on to my next task. See new post.