Unable to find these relays

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JamesDeRabbie

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Pround new owner of a 1980 c10 and am working through some issues now. This is the latest... Does anybody know what these are called and where to find replacements? They were fastened to the inside of the driver side fender. One is faulty and seems to have been causing my no crank no start. I jumped it and everything seemed to work fine. I've looked everywhere locally and I've flipped through the LMC catalog front to back and I can't find them! Anyone have an idea?
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Rickf

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Any thing that looks like a part number, might have to rely on google.
 
Old Guy Bill

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Start in the Reference section of this Forum, there’s a 1980 wiring diagram there. It’s extensive, but you’ll need to learn it if you plan on doing your own repairs.
 
dsteelejr

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I echo what @Old Guy Bill said, get a wiring diagram. I have an ‘80 K25 and I’ve been through all the electrical and never saw anything like that on the driver side fender. If it was related to a no crank issue maybe the PO installed it to have remote start. My K25 was my grandpa’s truck and he lived alone in a rural area so he installed a solenoid on the firewall so he could crank remotely from under the hood when no one else was around to help.
 
75gmck25

75gmck25

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They do not look like original GM relays.

The GM relay for the aux battery charging in my ‘75 K25 is silver and has a smooth, rounded case. It isolates the 2nd battery when you turn off the ignition, and then reconnects it to the alternator charge wire when you start the truck.

Anything mounted inside the driver’s side fender is likely to be for an aux battery, power to a camper, or power to a 7 wire trailer plug.
 
Grit dog

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Agree. Doesn’t look like anything I’ve seen and the drivers side fender is where the jack and tire iron is mounted. Nothing electrical up there.
When you say you jumped it, you jumped the wires at the relay or jumped the starter motor solenoid?
Sounds like got some wire tracing to do if you jumped the relay.
 
CorvairGeek

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That is some 80s variant of a GM Throttle Kicker / Fast Idle relay. They could actuate the fast idle from more than one input (ECM and HVAC control head). There are some variations in them (more than I know). I am skeptical that would be the root of your problem, unless it was someone (like me) that enjoyed repurposing OEM parts for their projects.
 
CorvairGeek

CorvairGeek

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I believe they were also used to control the EFE heater (heated grid under carb) on 250L6 and Buick V6s w/o FI.
 
dsteelejr

dsteelejr

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What wires went to that connector?
 
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