Hi
I have 1990 Toyota Camry. V6 2.5L (automatic) about 100,000 miles on it. My A/C light flashes intermittently on the on/off button for the A/C. If I play with it (turn it off and on several times) I can usually get it to go solid green and start cooling again. I went to check/change the A/C Magnetic Clutch relay under the hood and found instead a headlight dimmer relay in its place. When I went to purchase a replacement relay of the correct type (according to my manual and the relay box cover) the a/c magnetic clutch relay was an obvious mismatch. The manual states that for US cars it should have the a/c magnetic clutch relay and Canada cars should have a headlight dimmer relay in that spot. I checked the sticker in the car and it says Made in USA April 1990. The diagram is same as what is under my hood. Are the two relays interchangeable since it works with the dimmer relay in that spot?
I know that a slipping drive belt could be a culprit too.. that is next on my check list.. but am perplexed by the relay issue.
The dimmer relay in the spot now is square with 4 prongs (2 side by side..) When a/c light solid, the car cools well. Coincidentally, I went to local salvage yard and looked in other Camrys... They too had the headlight dimmer relay in the slot marked for the a/c magnetic clutch relay. What gives? Thanks for any help you guys can provide! Carol

Are your controls push button or lever controlled?




78 Corvette Pace Car For Sale-18k mi orig-Florida

My A/C on-off switch is a square push button (green light in center) and the temperature and vent location controls are sliders. I tried to attach picture of of underhood relay box.. but I guess it didn't work as I don't see it in the post. Prob doing it wrong but I'll try again now. Carol

Here is the location of your relay







78 Corvette Pace Car For Sale-18k mi orig-Florida

Yes. I know the location... But there is a headlight dimmer relay in the a/c magnetic relay spot. (like it were a Canadian car by my manual see my jpg attachment) I'm trying to figure out why it is there and when I tried to get correct relay per the manual/relay box lid... the supposed replacement relay not even a remotely close fit. wrong shape and prong size/placement. All the other relays in the car match the diagram and the relay box lid. Just the slot for the a/c magnetic clutch relay has a headlight dimmer relay in it instead.

How do you know it's a headlight dimmer relay?




78 Corvette Pace Car For Sale-18k mi orig-Florida

Touche! Guess I assumed it was headlight dimmer. (since the Canada made Toyota Camry should have a headlight dimmer there) I do see headlight relay elsewhere on the relay box. This relay in my car has this written on it:
Dimmer Relay (black square relay words on side)
oem#? 85926-30020
ND 05670-5081

It is plugged into the spot in the relay box marked for the A/C magnetic clutch relay. It is identical looking to the diagram I just attached. Please see my handwritten notation at the bottom. My car's relay cover shows same relay labels on the spots as the diagram from the manual. The problem seems to be when I try to buy a relay called " a/c magnetic clutch relay" that should be there ... the relay doesn't match size,shape, prongs or anything. (They try to sell me one that strongly resembles the round fuel relay- which def. doesn't fit.. similar prongs but wont go on)

Thank you so much for helping me if you can
Carol

It really doesn't matter what the relay says on it. A relay is a relay as long as the pins are set up and wired the same. Your most likely on the wrong track anyway thinking the relay is the problem. They had a lot of problems with the compressors on these. There is an RPM sensor in the back of it that senses clutch slippage and they have a lot of problems with that system. If the sensor signals slippage, the module shuts down and the light starts flashing.

If you want to know for sure about the relay, turn the box over and check the wire colors going into it.

Here is the wiring diagram






78 Corvette Pace Car For Sale-18k mi orig-Florida

Thank you for clearing up the relay question I had. I'll move on to the next step checking the belts and RPM sensor, compressor/clutch possibility. I'll post back my results after the hubby checks those (I can handle a relay but not major stuff).. Again Thanks for all the diagnostic help! Carol