Lexus LS400 1990 A/C is not automated... A/C Light blinks

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Hi all,

i have a 1990 Lexus LS400. my problem is that my A/C system is not automated. when i turn on the A/C it work and automatically shuts off from the thermostat and after few sec. and kick back on but this at point my A/C light blinks and the clutch not engaging (No A/C only the blower works) so i always manually off the A/C and on again.

A/C system is not automated like another system.

I really don't know how to explain but i did my best to explain it to you all so please help me fix this issue.


Thank you :)

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Hi...welcome to the Forum

It is either one of two things...

1. the air con system is low on gas

2. the air con relay has failed (common problem)  


After fitting you have to go through a reset on the air cond system and reset the engine management lamp if that has come on as well

Cheers  Trevor


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