Months ago I replaced the 2 brittle wires and dirty female spade connectors going from the Ignition amplifier to a 2 pin plug, which is then wired to the side of distributor, passing in to the reluctor. I marked the wires with tape. Months later when I got back to the job, the tape had fallen off. I don’t know which wire goes to which terminal on the module’s male spades that exit the amplifier. One male spade is normal width, and is marked ‘W’. The other male next to it is narrow width and marked ‘G’. The orientation of the module terminals exiting from the windshield side of the amplifier, are the wider male ‘W’ spade is closest to the middle of the engine, and the narrowest of these 2 spades ‘G’ is closest to the air cleaner. The wires attached to the module were a faded red, and a faded blue. They connect to a 2 pin plug. The colors change in the plug, on their way to the reluctor, so that the red wire becomes a faded orange and the blue becomes a faded (or dirty) beige. The factory shop manual schematics does not help me ID these wires. A thorough Internet search doesn’t help either. 1985 US spec XJS HE. Help!
if I understand your post stands to reason the narrow connector goes on the narrow connector on the other wire same for the two wide connectors. Maybe I missed something in your post but seems pretty simple to me.
Originally, the amplifier had a plug that contained the red and blue wires which fitted into the amplifier, and then went to the distributor. Before I got the car, somebody removed the plug and replaced it with 2 standard female spades, and used wire that was not the same color as the original red and blue Jag wires. I replaced the spades and wire since they were corroded. Although I ID’d the wires with tape, it came off later on, before I could re-connect the spades to the amp. So now I have 2 standard sized female spades, both of which will fit onto the module’s spades, even though module spade (G) is thinner than module spade (W). My replacement new wiring was spliced onto old faded red and blue factory wires. I need to find out which module spade the red and blue wires are supposed to go to. Thanks for your help.
I had that problem once, but I figured it out by having a second AB14. Not sure what system you have (mine was late S3 XJ6) but I remember my research suggested that the ignition timing changes depending on the polarity of the reluctor’s connection. The correct polarity gives the more retarded timing. Not sure of this–a long time ago.
Thank you. I read that as well. I also read that connecting the 2 distributor reluctor wires incorrectly will allow the engine to idle, but not rev. If I did that test and the engine wouldn’t rev, then I would know that reversing the wires would be the answer to my problem. However, I hesitate to do that test because the amplifier module also sends a signal to the ECU, and is also connected to the low voltage side of the coil. I’m concerned that if I do that test and in doing so connect the reluctor to the amp module in the wrong order, perhaps a feedback voltage would be sent to the ECU and damage it. I’d hate to lose an expensive ECU due my ignorance.
I don’t believe the reluctor connections can influence the ECU signal in any way – other than screwing with the timing or not providing a signal at all. The reluctor is an input, the ECU signal is an output, and there’s a big fat resistor in that output to make sure no serious currents get through.
Still, I suppose you could just disconnect the ECU and then see if you get spark while turning the engine over on the starter. If you do, it can’t be too far wrong.
BTW, the theory on that pickup is that the point of the star wheel moves closer to the pickup, then passes it and starts moving farther away. The change in magnetic field generates a voltage in the coil, and when the pickup stops getting closer and starts moving away, that voltage is suddenly reversed. The amp senses the voltage reversal. If you hook it up backwards, you get a voltage reversal the wrong way, which the amp doesn’t recognize. So, it picks up the voltage reversal that happens when one point of the star wheel moving away from the pickup is replaced with the next point moving toward the pickup – quite a few degrees off, either advanced or retarded depending on which terminal in the cap gets the spark that’s waaaay off. And the spark might not occur at all, since the point moving away is generating an ever-smaller voltage and the next point starts out with a weak voltage at first, so the voltage reversal is weak.
BINGO!! Thanks so much. That pic did it for me.