Litvin62

I jumpered both my ac pressure switch and my cycling switch but the compressor clutch still won't engage, and to check to make sure the compressor clutch worked I hooked it right up to the battery and it engaged fine, I'm also getting zero volts at the connector going to the ac clutch, any suggestions?

jstaszko

I know this is an oooold thread but I could use some of the same help.

Here is what I've done, engine running, Max AC, clutch will not engage compressor:

• Jumpered low pressure line switch
• Jumpered high pressure line switch

Where are the switches located?

mattpatt01

I Am in the same boat! Where are these switches located on the MK-13 F-150's?

Todd Adams

Here's a pic for more on relays and fuse's

former radar tech

Replaced switches, relay, and connector. I can force the clutch to engage with a jumper in the relay socket. With the relay removed I get 12 volts on the relay coil pins. When I insert the relay, I do not read 12 volts across the coil. I read 12 volts from the ground side of the coil to ground. Coil reads about 150ohms. Clearly some problem between the ground side of the coil and pin 18 of the pcm or a bad pcm as I see it. Any suggestions or confirmation of my conclusion?

ProjectSHO89

Are we supposed to just guess as to what you're working on?

former radar tech

2006 F150. AC Clutch not engaging.

ProjectSHO89

Did you check to see if the PCM is receiving the correct input(s) needed for it to decide to energize the clutch relay?

Check continuity of the coil relay low side to pin 18?

Gotta think at the system level.... can't just hyper-focus on individual components.

Manual or automatic climate control?

liteflyer

By accident I found that if the engine is rough running or has a miss, the computer will shut down the A/C clutch from engaging. A bad coil or injector wire connector can do this as well as a bad coil or injector themselves.