I'm working on my mother in laws 98 Accord. The AC cuts off and on (mostly off) I noticed that the fans would cut off and on. So I tried to check the relays under the hood. They all seem ok BUT here's where it gets weird this blue and red striped wire hooked up to the (whatever its called in the picture), when I poke the test light to it, the fans turn on and the ac stays on...any ideas?

 

that is the pressure cut off switch. I beleive its either high presusre or a 3 way where it will cut the ac off if pressure is too low or too high.

 

nest thing to do: connect an a/c line pressure guage that you can get at walmart or any automotive store like autozone to the LOW PRESSURE side only. That will tell you the charge state(pressure) of your a/c system. remember to have the a/c on full blast recirculate to get a correct reading.

 

sounds like a lack of ground .........when you are hooking up the test lite to the red/blue wire you are giving ground to the system .....

DO not waste your time checking the pressure ,, most likely you got a bad
thermostatic switch located in the evaporator

 

Well, after reading this, it sounds like the pressure switch is cutting off and on. So this could be the low freon? Low freon could be that its leaking? OR this can be a bad switch...

 

Dont waste your time checking pressures, where did that come from, every AC man wants to know both pressures every time but sometimes only the LO pressure will suffice, we need pressures to help better, with only two wires on the receiver drier it is the HI pressure cutout switch, and yes you are grounding it, go to autozone and get the pressures checked with the system running, it sounds like you will have to use your test light to get the system to work.