Help locating correct "pin" to jumper on ac relay


New Member
Apr 5, 2020
2016 5.0. I'm trying to use a wire to jumper the ac compressor clutch to engage to diagnose why my ac is blowing warm air but not sure which holes to stick the wire in. There's no diagram on the relay. The fuse and relay are both good. The compressor doesn't engage. It's a 2016 so I can't image it's that low on coolant but who knows these days.
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Active Member
Apr 5, 2020
Woodstock, GA
The clutch uses 12vdc, to engage the clutch. The low pressure switch controls the coil of the relay via ECM. Coil closes the contacts of the relay, suppling the voltage for the clutch.

With the power plug removed form the clutch, using a meter set to 12vdc, black probe to ground.

Set the ac on, ignition on, put red meter lead into pin of the plug removed. If no voltage is found the low pressure switch is detecting low freon .

Find 12vdc the clutch on the compressor is toast. To confirm, leaving the black led connected to ground . Set meter to OHMs, probe the male pin on the compressor. You should get a reading, it will have some resistance. If no reading the clutch is toast, coil is open.

My guess 2016, low freon, no voltage on the female pin of the plug removed from compressor .

It could also be a bad really......