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andrewo
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I know that this was covered ad nauseum on the old board, but I never printed it out. Can someone tell me how to defeat the ignition interlock and buzzer? As I recall, it involves pulling the logic box plug and jumping two posts.

Thanks - Andrew

Mark Rosenbaum
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Yep, that's all.  Pull the round plug, then jumper pins 11 and 12.  This connects the START wire from the ignition switch to the hot side of the coil on the relay used to activate the starter solenoid.

Alternately, pull the round plug, then connect pin 12 to an 'Engine Start' pushbutton such as that used in the Honda S2000.  The second side of the button would be wired to a source of switched or direct battery voltage, perhaps with an added inline fuse.

Attachment: red button.jpg (Downloaded 153 times)

andrewo
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Okay, I have placed a wire connecting those two, but do I need to do it in a way that allows the plug to go back in? I assume that there are other things running through that plug. Should the car be able to start with the plug out and the jumper in place?

Thanks - Andrew

Mark Rosenbaum
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With pins 11 and 12 jumpered, and with the round plug disconnected and in a plastic bag to avoid short circuits, the car will start and run normally.  However, you will lose the functions of (a) the 'door open and key in ignition' buzzer, and (b) the 'fasten seat belts' warning light and buzzer.

If you're comfortable with altering the car's electrical system, you can remove all of the wiring associated with the infamous seat belt warning system and make a permanent connection between the wires that once ran to pins 11 and 12 of the round plug.  This involves unwrapping and rewrapping the wiring harness, and therefore is most easily done when the dash has been removed for some reason.  You'll want to save the blue tape used to wrap the wiring, as it can be re-used once cleaned of dust and grime.  IIRC this tape is also available from British Wiring.

The 'door open and key in ignition' audible alarm can easily be restored.  The buzzer used on European JHs for this purpose was still available from Delta Motorsports a few years back, and as it's unlikely this is a fast moving item, they should still have plenty on hand.  Alternately, you could use a junkyard / aftermarket chime, buzzer, bell, horn, or whatever else suited your fancy.

The 'fasten seat belts' function can be restored if one adds the appropriate (but expensive) aftermarket gadgetry.  Alternately, you could make contact with JH owner Frank Schwartz, who some years ago was looking into designing a circuit for the task.

However, a better use for the warning light might be to provide some new function such as indicating low oil pressure, low fuel level, hood or trunk lid ajar, door ajar, or whatever else suited your fancy.  The legends giving the functions of the warning lights are thin plastic films, clear text on black background, and if you have access to a laser printer that will deal with transparency films, you can make new legends with whatever text you wish.  Wiring, of course, would depend on what you had in mind.

 

Spaceman
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that makes no sense, your WR wire from ignition goes thru the round plug, therefore it needs to be plugged back in for the voltage from the key, to get to the seat belt relay?

redracer
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Actually it does work: the WR wire goes through the "LOGIC" box to see you have all the necessary items hooked up, such as your seat belt on and the door closed, so the current can go back through the #12 wire to the relay by your left knee and onto the solenoid on the starter.
Basically, you are cutting out this "Ralph Nader" garbage(like the pressure differential switch which has been described as well in another article I wrote years ago).
This was written up over 40 years ago in the WHITE LADY magazine and almost every car I have seen or worked on will have this done.

noomg
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Andrew,

You still have a function interlock system in your car?



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