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M22_COBRA
04-13-2025, 12:37 PM
Gen 3. Coyote, RF harness, GPS gauges

Trying to figure the purple Tach Wire, even after reading threads, and trying to figure out if I'm setting myself up for failure with my sending unit harness placement.

If I understand correctly, the yellow wire of the tach goes to this purple wire in the RF loom here.
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The purple wire then connects here at the weather pack then terminates at the this blunt end. Is this blunt end what I'm to splice into the engine harness coil of my choice? Referencing EdwardB's build....
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I've run my sending unit harness down the DS main rail, is this a party foul? Am I setting myself up for failure here? Should I add the purple Tach wire to the sending unit harness and drape it over the top and run the wires down? I think that's in the instructions, but they also show the purple wire as part of the RF harness??

Lastly, I know the blue goes to the starter request, but what are the grey and green "speed sensor" for? Both Speedo? Or not necessary since coyote PCM and GPS gauges?
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M22_COBRA
04-13-2025, 02:23 PM
Or should I just run the yellow tach wire with the sending unit harness over the top of the engine and call it a day?
toadster
04-13-2025, 04:42 PM
yes splice the purple blunt end into one of the cylinders, i ran my harness over the DS valley as well - spliced into cylinder #8, closest to the driver
it doesn't matter which cylinder, any will work

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M22_COBRA
04-13-2025, 04:59 PM
10-4 on that.
Any verdict on the grey and green "speed sensor" wires? I don't have a mechanical sending sensor so....? I'm thinking they are not useful for my application since I have GPS?
Blitzboy54
04-14-2025, 06:40 AM
10-4 on that.
Any verdict on the grey and green "speed sensor" wires? I don't have a mechanical sending sensor so....? I'm thinking they are not useful for my application since I have GPS?

That is correct. If your using GPS you have no need for the mechanical sender.
M22_COBRA
04-14-2025, 07:07 AM
That is correct. If your using GPS you have no need for the mechanical sender.

ALRIGHT! Lets go boys!
dbo_texas
04-14-2025, 01:36 PM
10-4 on that.
Any verdict on the grey and green "speed sensor" wires? I don't have a mechanical sending sensor so....? I'm thinking they are not useful for my application since I have GPS?

I think I repurposed those for my reverse lock-out module. Routed to the transmission sensor.