Bad ignition switch?

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AZ Highlander

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My sons K 20 has problems with ignition. They are only getting one volt to the distributor. The 16-year-old pulled the ignition switch and in the run position all were at zero ohms, which he thinks should be correct.
He reconnected the ignition switch at the column and was getting full battery voltage on the three places in this photo where his fingers are pointing to.

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The two silver prongs in the photo below that his thumb is pointing to should be getting a good ground from the column in the start position.
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The four other pins should be getting full battery voltage when in the start position but they are only getting one volt just like the distributor wire told us at the beginning.
Is the ignition switch bad and should we just purchase a new one to replace it with?
 

Jgonick

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i vote bad switch. They are roughly $20 anyway.

The four other pins should be getting full battery voltage when in the start position
based on your picture-
I think
bottom left (sol) - gets volts in start position - starter
top left (ign 1) - gets volts in start & run positions- includes you distributor
bottom right (ign 3)- gets volts in run position
top right (acc) - gets volts in run & acc positions
 

AZ Highlander

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i vote bad switch. They are roughly $20 anyway.


based on your picture-
I think
bottom left (sol) - gets volts in start position - starter
top left (ign 1) - gets volts in start & run positions- includes you distributor
bottom right (ign 3)- gets volts in run position
top right (acc) - gets volts in run & acc positions
Thanks. All of those should be getting full battery voltage however, correct?
 

Ricko1966

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Plug the ignition switch back in ,run it through its travel with an awl,a screwdriver a nail whatever. If the truck starts and runs I suspect the ignition rack.
 

AZ Highlander

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Looks like it may have been a bad ignition wire solder. Stay tuned
 

Gpaw44

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Where do you get an ignition switch. I don't think you can get a new deco switch or I have not ben able to find one. I have bought 2 at different parts houses and had to take them back. One the pins were wrong and the other one I could not get my plug to fit through the metal frame. I need up using my old one.
 

AZ Highlander

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Where do you get an ignition switch. I don't think you can get a new deco switch or I have not ben able to find one. I have bought 2 at different parts houses and had to take them back. One the pins were wrong and the other one I could not get my plug to fit through the metal frame. I need up using my old one.
O'Reily's had them
 

AZ Highlander

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K15 (aka V1500)
Engine Size
350 (5.7L)
Plug the ignition switch back in ,run it through its travel with an awl,a screwdriver a nail whatever. If the truck starts and runs I suspect the ignition rack.
Would the ignition rack cause only 1v to get to the distributor wire?
He just replaced the pinon because he broke the plastic during column disassembly. The pinon came with a new rack, but not sure if he replaced it or just reinstalled the original.
 

Ricko1966

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Would the ignition rack cause only 1v to get to the distributor wire?
He just replaced the pinon because he broke the plastic during column disassembly. The pinon came with a new rack, but not sure if he replaced it or just reinstalled the original.
Lots of things can cause it. Yes the linkage in the column could cause it.and try running the truck via a awl in the switch would be a good diagnostic move
 

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