Sniper won’t shut off

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Anvil-3
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Sniper won’t shut off

Post by Anvil-3 » Fri Feb 04, 2022 12:29 pm

Hi everyone,

After a year sitting and getting the Jeep together again I got it fired up on a 2bbl sniper with ignition box and distributor. It’s all hooked to a keyed ignition that went to the old ignition box. The sniper turns on and off as it should with just battery power.

However once it was actually fired up and running the key is unable to shut it off and I have to disconnect power to the ignition box to get it to stop running.

Has anyone experienced this? Both my pink wires and red for the ignition box all go to the same switched ignition.


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Current rigs
1989 Grand Wagoneer, inop
2014 HH-60M
Former rigs
2000 XJ, 4.0, aw4, np231, 31's (totaled)
2000 xj 4.0, aw4, np242, 37's (sold, then totaled)

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Stuka
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Re: Sniper won’t shut off

Post by Stuka » Fri Feb 04, 2022 2:09 pm

Sounds like the alternator is feeding in some place past the ignition switch.

Or the switch itself is bad maybe?

If the engine isn't running, and you turn the switch to run, and then back to off, does the sniper still have power going to it? If not, its probably the alternator back feeding some place.
2017 JKU Rubicon Lifted and stuff
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ


DesertCJ5
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Re: Sniper won’t shut off

Post by DesertCJ5 » Sun Feb 06, 2022 7:50 am

This should workImage


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DesertCJ5
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Re: Sniper won’t shut off

Post by DesertCJ5 » Sun Feb 06, 2022 7:50 am

Image


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tgreese
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Re: Sniper won’t shut off

Post by tgreese » Wed Apr 27, 2022 11:02 am

Long past this post ... however, I've seen this problem before. Originally, power for the module and the coil comes from the ignition switch. There is a resistance wire in-between the ignition switch and the alternator exciter connection on these Jeeps. This blocks the back feeding from the alternator to the ignition switch enough to shut off the original ignition in the Jeep.

With a system like the Sniper, it uses the ignition connection only as an on-off signal, and has a separate battery connection that supplies power to run the control unit. The trickle of current back through the resistance wire is enough to keep the Sniper switched on. A diode will block that signal completely.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
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