ok, i bought my truck it was missing the condensor. i installed a condensor charged the system. i have a 95 rodeo btw. i cant get the a/c to kick on. i checkd the fuse and relay in the main fuse box there all good. i hooked the comp directly to the batt for a few secounds and it kicked on and was blowing very cold. so somehow im not gettin power to the compressor. anyone know what to check, and where to locate what i need to check. thanks.

THERE IS A HI PRESSURE SW IN THE HI SIDE LINE EITHER ON THE CONDENSOR INLET PIPE IT IS A DUAL ACTION SW OR IT MAY BE MOUNTED RIGHT ON THE REC/DRI, IT WILL SHUT THE COMP OFF AT 30 PSI LOW PRESS AND ABOUT 330 ON THE HI SIDE, JERRY

i tried jumping the switch someone said on here and it didnt make any differance. it plugs right in the dryer

OK LETS TRY THIS FIRST, REMOVE THE GLOVE BOX ,ON THE A.C EVAPORATOR, THERE IS AN ELECTRONIC THERMOSTAT, UNPLUG THIS UNIT , USE A JUMPER ON THE GRN/RED WIRE TO THE WHT WIRE WITH THE BLOWER SW IN THE ON POSITION, THIS WILL CLOSE THE AC THERMOSTAT RELAY , SENDING CURRENT TO THE AC COMPRESSOR RELAY CONTACTS, IF THE AC INPUT SIGNAL IS GETTING TO THE ECM, THIS SHOULD NOW GROUND THE AC COMP, RELAY COIL AND SEND CURRENT TO THE CLUTCH, THIS IS ASSUMING THAT THE AC SW IN THE DASH IS WORKING , IF THE CLUTCH NOW ENGAGES TURN THE AC SW ON AND OFF, IF THE CLUTCH GOES ON AND OFF YOU HAVE A BAD THERMOSTAT ON THE EVAP HOUSING , GIVE THIS A SHOT JERRY

thanks, im going to give this a try later today. i let you know.

ok tried this and nothing. but im now reading 20psi with the comp off. is this to low for it to kick on? also whats next toi check. the a/c switch? how hard is that to check, aong with whatever else down the line to check.

ok i checked the a/c switch, that is good. i got the dryer and condesor from junk yard. is it possable a bad dryer will do this? so im gettin down to the nitty gritty here. now is the relay in the fuse box the same relay as the thermo switch relay. if not where is this relay located? i only tested the relay in fuse box. also with system off it has 25 psi. now when i put a can on it it doesnt kick on. it should kick on as soon as the pressure hits right? this thing is bugging me i really cant afford for a shop to fix it.

YES IT IS TOO LOW TO TRIP THE LOW PRESS SW IT USUALLY TAKES AT LEAST 30 PSI STATIC PRESS, JERRY

THE AC THERMO STAT RELAY IS MOUNTED BEHIND THE METAL PLATE RIGHT TO THE REAR OF THE MAIN FUSE BOX, THE COMP RELAY IS IN THE FUSE BOX, TRY THIS , GO TO THE TRIPLE PRESS SW ON THE REC/DRI AND UNPLUG IT CONNECT THE BRN WIRE AND THE GRN/BL WIRE TOGETHER AN D SEE IF THE COMP KICKS ON YOU MAY HAVE A BAD PRESS SW IF IT IS A JUNK YARD PART ,THOSE SW CAN STICK INTERNALLY IF THEY HAVE NOT BEEN USED INA LONG TIME JERRY

the pressure switch was the first thing i tried. ill try the relay behind the fuse box. what else if not these 2 things can it be, do i need to just run new wiring to everything. maybe something is cut or broken somewhere? ive just about tried everything.