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Power Seat Problem, Need some help.

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Old 03-02-2013, 08:33 AM
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Power Seat Problem, Need some help.

I don't know what to try next. I have a short somewhere, just don't know how to track it down. I checked the fuse for the drivers seat and it was blown. I stuck a new one in and the thing blew as soon as I stuck it in. I disconnected the seat motors, plugged in a fuse and it blew again as soon as I stuck it in. Any ideas on how to track this down?

I don't see any worn or shorted wires under the seat. I checked under the passenger side kick panel per another post I found, but that looks fine. I don't know where to look or what to test. I'm weak on electrical trouble shooting so any advise is appreciated.

Thanks!
 
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Old 03-24-2013, 02:01 PM
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Probably the switch is shorted inside. My seats wouldn't move at all, so I tore it all down, electric motors and all. Just to figure out the switch was only allowing 5 volts to the motors. The switch eventually shorted out completely and would pop the fuse.
 
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Old 03-24-2013, 02:12 PM
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Thanks! As I can't find any obvious shorts, that sound plausible. Any way to check just the switch? I'm thinking of checking continuity. Would that do it?
 
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Old 03-24-2013, 02:24 PM
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Pull it out and hook it up outside the seat. Yes check continuity, and measure the voltage to each terminal. One will be the power source, and the others should light up when pressing the switch. I still haven't bought a switch, if the seat needs moved I use a socket, but the motors arent hooked up either. My seat needs redone so it's either getting swapped or rebuilt when funds allow.
 
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Old 03-24-2013, 05:34 PM
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Thanks again! I pulled the switch. Con't hook it up outside the seat to check voltage as the fuse blows as soon as I stick it in, so not voltage through the wire. I did check for continuity from the fuse pole to the green (power) wire at the connector to the seat. Looks good, so the short it at the seat somewhere. When I checked the switch out it is contrary to what I would think with my limited electrical knowledge. I get continuity between the power and each of the poles WITHOUT pushing any switches at all of them except for the forward reverse switch. With that on I have to move it to get continuity. With the others, I break continuity when depressing the switch.

Is the switch benching out correctly? I'm thinking there should only be continuity when switch is depressed. Is my thinking correct. Is an internal short in the switch my problem?

Thanks
 
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Old 03-24-2013, 09:33 PM
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That switch is toast. You're right, there should only be continuity when a button is pressed. Put a new fuse in and Take a jumper wire to the plug and see if you can make the seat move that way to be sure. If you put one end in the power terminal then touch the other terminals it should move the seat. Also, do a continuity test from the power wire to ground. There should be none. If there is then the power wire is grounding out somewhere and could fry the switch. Most likely the switch just gave up.
 
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Old 03-24-2013, 11:08 PM
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Awesome. Thanks for all of your help. I'll post back once I get it working.
 
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Old 03-25-2013, 08:59 PM
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Damn!!!! I thought I'd try the hot wire routine so I could see the seat actually move for the first time since I've had this truck. Stopped on the way home from work and picked up a fuse, got home, stuck it in and POP. Blew as soon as I stuck it in. I don't even have the seat switch in at this point as I am waiting for the replacement.

I have not done the power wire to ground continuity test, but it is certainly looking like I have a short in that circuit somewhere even though I have continuity from the fuse.

I figure I will try unplugging the the adjustable pedals and see if it may be there first (check the switch as well), but at this point I'm thinking it will probably be easier to run a new wire. It will be easy enough to cut and splice a wire at the switch connectors, but what about the Fuse Box/Power Distribution box. I've never had one of those out. Do wires plug into the bottom of those, or would I need to do a cut and splice at that end as well?
 
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Old 03-29-2013, 05:33 PM
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Fixed it by running a new wire. Pulled up the Power Distribution box and splice in a new wire under that. Then ran it to the pedal switch and seat switch. So nice that it came to life. I've had this truck for a couple of years and this is the first time the seat or pedals have moved. Pedals were stuck in the up position, much more comfortable now that I can move them all the way down (I'm 6'4").

Anyway, the seat moves up and down fine, just not back and forth. Just makes a rumbling sound (motor turning but not engaging). Anyone taken a seat motor assembly apart? Is it a gear that may have slipped out of place, or stripped gears? Any ideas are appreciated.
 
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Old 03-29-2013, 06:58 PM
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a "power-probe" can really help in circumstances like these, it connects directly to the battery + and a ground, it will test for continuity +voltage or +ground, + will add voltage to the circuit if desired, saves a lot of time compared to a standard test light. i got mine used from the Mac tool truck driver for 65$ a few years ago, so I'm pretty sure there must be cheaper alt's out there. I was a little to late to help you.... but maybe it will save some one else a couple hours
 
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