XJ6 & XJ12 Series I, II & III 1968-1992

Testing The Diode Pack

Old 06-14-2014, 08:19 PM
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Default Testing The Diode Pack

Hi Again,
I'm Using my S 57 manual to test the wiring to resolve a rich running engine.
Tonight I remembered, somewhere, I read a thread from a gentleman named Frank, who mentioned a bad Diode Pack could enrich fueling. I think it had something to do with sending the computer an incorrect signal. So I tested the diode pack:

Using a Fluke model 77 multimeter, here are my results:

Pin 2 to Pin 5: 0.550, one short beep

Pin 3 to pin 5: 0.554, one short beep

Pin 1 to pin 4: 0.000, continuous tone.

Now, according to the Fluke 77 Operator's Manual, Pin 1 to Pin 4 is indicating a short circuit, so Believe I need to replace the diode pack.

I value all of your opinions on this matter. Please tell me I'm correct.

If this fixes the problem, (after I'm done crying) Tammy and I are going to celebrate. We going to take the jag out for fish 'n chips, and a pint of bitters!
Thanx for listening!
Old 06-14-2014, 10:20 PM
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The diode pack doesn't have anything to do with lean/rich fueling nor send any signal to the computer. It controls the fuel pump circuit and acts as junction point for a couple other items.

Here's some reading on rich mixture problems:

XJ6 Series - EFI Rich Mixture

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Mad Matt (06-15-2014)
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