92 Sc400 A/c Light Blinking

nichola1 · July 21, 2009

When I start the car sometimes the ac light blinks and compressor stays off, sometimes it operates normally (blows cold air). When I was driving on one occasion when it was blinking I hit a speed bump and the compressor kicked back on the light stayed on...any thoughts?

arielscar · July 22, 2009

Most likely a bad AC compressor; I had similar problem and a blinking AC light. Look around for a reliable AC compressor rebuild service for your unit (assuming it's original unit) rather than putting an exchange unit on.

lexussuvlvr · July 26, 2009

yea. It's a bad A/C compressor. My 1992 SC400 I had had the same problem. I took it to the dealer to get it fixed. But i would never do that again. they charge an arm and a leg for it. :wacko: best to find one online, buy it, and go to a mechanic.

sc400InTraining · July 22, 2011

yea. It's a bad A/C compressor. My 1992 SC400 I had had the same problem. I took it to the dealer to get it fixed. But i would never do that again. they charge an arm and a leg for it. best to find one online, buy it, and go to a mechanic.

So yea... Sometimes I wonder about ppl here and the way they just love to take it up the A## with out so much as looking into the problem themselves.

Oh well thats why Im here...

So that blinking led light you see doesn't necessarily represent a bad compressor what it's telling you (with out explaining the wiring nitty griity) is that there is no relay connection being detected which "charges" the compressor(blow cold air) so you may actually have a magnetic clutch relay or bad/old wiring you can test this hypothesis by connecting a temporary lead(12 guage wire and two alligator clips) from the the positive side of the car battery and attaching it to terminal 3 of the magnetic clutch relay. The relay should be the only connection of wiring you see right there above the compressor. Before doing this make sure there is freeon in that baby and you turn the A/C on full power and that the negative side of the battery is grounded(the "thingy" is connected), also becareful of the drive belt that sh*t is a hoss!

sc400InTraining · July 22, 2011

yea. It's a bad A/C compressor. My 1992 SC400 I had had the same problem. I took it to the dealer to get it fixed. But i would never do that again. they charge an arm and a leg for it. best to find one online, buy it, and go to a mechanic.

So yea... Sometimes I wonder about ppl here and the way they just love to take it up the A## with out so much as looking into the problem themselves.

Oh well thats why Im here...

So that blinking led light you see doesn't necessarily represent a bad compressor what it's telling you (with out explaining the wiring nitty griity) is that there is no relay connection being detected which "charges" the compressor(blow cold air) so you may actually have a magnetic clutch relay or bad/old wiring you can test this hypothesis by connecting a temporary lead(12 guage wire and two alligator clips) from the the positive side of the car battery and attaching it to terminal 3 of the magnetic clutch relay. The relay should be the only connection of wiring you see right there above the compressor. Before doing this make sure there is freeon in that baby and you turn the A/C on full power and that the negative side of the battery is grounded(the "thingy" is connected), also becareful of the drive belt that sh*t is a hoss!

I just remembered something else....

There is this thing called a compressor lock sensor which causes the A/C button to blink if:

your engine rpm is higher then like 450 or something.

and the timing between the compressor and engine is rpm is off.

So what you could do is adjust the tension on the drive belt to put them back in sync(take a crow bar to the tensioner have a friend help!)

Also the Compressor lock sensor could be faulty that thing is right next to the relay clutch and is only a two terminal connection where as the Magnetic Relay clutch is 4 terminals

sc400InTraining · July 22, 2011

yea. It's a bad A/C compressor. My 1992 SC400 I had had the same problem. I took it to the dealer to get it fixed. But i would never do that again. they charge an arm and a leg for it. best to find one online, buy it, and go to a mechanic.

So yea... Sometimes I wonder about ppl here and the way they just love to take it up the A## with out so much as looking into the problem themselves.

Oh well thats why Im here...

So that blinking led light you see doesn't necessarily represent a bad compressor what it's telling you (with out explaining the wiring nitty griity) is that there is no relay connection being detected which "charges" the compressor(blow cold air) so you may actually have a magnetic clutch relay or bad/old wiring you can test this hypothesis by connecting a temporary lead(12 guage wire and two alligator clips) from the the positive side of the car battery and attaching it to terminal 3 of the magnetic clutch relay. The relay should be the only connection of wiring you see right there above the compressor. Before doing this make sure there is freeon in that baby and you turn the A/C on full power and that the negative side of the battery is grounded(the "thingy" is connected), also becareful of the drive belt that sh*t is a hoss!

I just remembered something else....

There is this thing called a compressor lock sensor which causes the A/C button to blink if:

your engine rpm is higher then like 450 or something.

and the timing between the compressor and engine is rpm is off.

So what you could do is adjust the tension on the drive belt to put them back in sync(take a crow bar to the tensioner have a friend help!)

Also the Compressor lock sensor could be faulty that thing is right next to the relay clutch and is only a two terminal connection where as the Magnetic Relay clutch is 4 terminals

last edit promise...

The magnetic relay clutch is located at Relay Block 2 which is under the hood to your right (if you are standing in front of the car) with two screws that keep it closed.