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View Full Version : 93 240 AC problems: won't switch on.


allh0pelost
09-13-2007, 03:53 PM
i'm sorry if this has been posted on this forum before, but i just looked through all of the archive and faq section and didn't find anything on the AC system. also, the search on this board finds the word "AC" to be too short to search for.

anyways, here's the low-down. i have a redtop SR in a 93 240. AC worked fine when i first got the car, then the belt snapped off. i didn't mind cause i wasn't using the AC anyway (it was during winter). jump to today and it's hot as balls in florida. i install a new belt expecting my AC to work, and it won't power on. the green light on the control panel doesn't light up. i check the fuse under the dash and it's fine, i tested the relay under my intake and it's fine. then i tested the voltage from the switch to activate the relay, and i was getting nothing, well, a reading of .01v that stayed the same whether the switch was on or off. so i googled around for AC problems and found that there is some weird thermistor device behind the glove compartment that occasionally has bad soldering joints. i checked my device for bad soldering and it was fine!

i need to know, is there anything else that would cause the AC switch to not send a signal to the relay? does the ECU control this? is there a sensor that is saying "ACCESS DENIED!" it's really hot here in FL, and i hate going to class all sweaty... the girls think it's gross.

so if anyone could help me, please! before i drown in my own sweat!

orion::S14
09-13-2007, 07:48 PM
Triple pressure switch.

If there is no R134 pressure, then the compressor will NOT turn on.

Get one of those $10 gauge setups, and check to see if there is pressure in the system.

- Brian