ls400beast

Ok so summer time is here and its really hot in AZ. Unfortunately my ac does not work i was able to check the pressure. i then decided to take it to my local shop to get it check our on the basics oil freon compressor functionality etc. When the mechanic finished he said that it was fine and he could not figure out why it wouldn't blow cold i then decided to do a diagnostics tes on it that i found on lexls.com and returned with this error 34 - Open in air inlet damper position sensor circuit. Or, open or short in air inlet sensor servomotor circuit. Or, air inlet servomotor locked i need help understanding what it means. i did what you call a self-diagnosis and i think its the ac control panel i have checked all fuses but have not checked all relays it seems that when ever i turn on the ac it turns on but turns off a little while after about 10seconds.i would really appreciate if some one could help me figure out what that code means thanks and i looking forward to your reply

fixmiester

Not familiar with a '90, but the servomotor in question determines where the blower is getting air from; either the heater core, or the evaporator core, or a mix of both, depending on user control settings. If it is broken/stuck, it may not be pulling air through the evaporator. Thus, the evaporator is getting too cold, and the compressor is told to shut down. If you don't feel cool air with the compressor running, see if your high pressure line is hot (ten seconds of run time won't produce much heat, though) but it will confirm you have some heat transfer trying to happen. You may also feel some coolness at the evap lines near the firewall. This means freon is being pumped, but if your blower is not drawing air across the evap, or the evap is blocked with debris, your system will not blow cold air. Check the forum for air-damper location and troubleshooting.

qha_vn

code 34 refers to air inlet servo motor which controls outside air or inside air intake selection. it does not play a role in blowing cold air or not.

1- does it blow air (no matter cold or hot) thru the vent when you turn A/C on?
2- if it does blow hot air when you set temp to low or max cool, most likely compressor doesnot work.

ls400beast

ok so i got the compressor To work and all and it worked for about 2 days when i turn the a/c on it automatically turns off anut 5 second and the ac blinks i have no leaks and i know my compressor is not the problem buy something is telling the compressor to shut down right after i turn it on sigh