95 corolla a/c button flashes 1.6L

A flashing A/C button means that the system has detected a difference between compressor and engine RPM and has disengaged the compressor clutch. Check to make sure that the compressor drive belt is not slipping. If not, then check the RPM sensor on the compressor to make sure a signal is coming out.

It means the R134a level is either too high or too low. Go to an AC shop ...

Hey Ray O, I checked for the clutch speed sensor and there is no sensor on the compressor. It has only 1 wire going to the clutch.I did'nt find an engine rpm sensor either. It has a distributor. By the way, a sticker on the hood says its a 1.8L, is there a difference? It has a 4 wire pressure switch on the high side line going into the evaporator all different colors. I'll keep looking. Thanks.

The 93-95 Corollas (Generation 10 or AE10x) came with 2 motors. 4Y (1.6) and 7Y(1.8) 3 transmissions, 5-speed manual and 3 and 3+OD auto trannies. Between my sister and myself we own 3 of the 1.8 w. 3+OD transmissions. It should be identified as part of the VIN.

Charles of Schamuburg

The RPM sensor is not on the clutch, it is on the compressor itself. Disconnect the electrical harness going to the compressor itself - I think it has 4 wires. On the pigtail coming out of the compressor, measure the resistance between the top 2 terminals closest to the locking tab on the connector. Resistance should be between 165 and 205 ohms.

I think there is a sight glass on top of the receiver/drier in front of the evaporator. When you look into the glass with the compressor engaged, it should look like clear water flowing past, with very few bubbles. If you see foam or nothing flowing past then the refrigerant charge is too low and needs to be recharged. Low refrigerant levels will keep the compressor from engaging.

The corolla is a DX 1.8 with a 3 speed auto-no OD. I pulled out the engine/trans about 2 years ago when I rebuilt the trans. I checked the compressor and there is no 4 wire plug, only a blk/red wire. I applied voltage to it and the clutch engaged. The rec/dryer is located in front of the condensor on the battery side. I tested the ac when I engaged the clutch for about

1 minute, it cools normally and full of l34A. I'm about 10 miles from the Mexican border here in S. Texas and it was 94 degrees today. Gotta get it going soon. Thanks.

Hmmm....

The engine and transmission should not have any bearing on the flashing A/C light unless the pulley diameter on the engine and/or compressor is incorrect. If the A/C worked for a while, then this is not the case.

AFAIK, the only thing that makes the A/C light flash is if the RPM sensor on the compressor detects a different speed from engine RPM and it has de-energized the compressor clutch. This sometimes happens when you drive through big puddles and water makes the compressor drive belt slip. It will also happen if the drive belt slips or fails or something in the compressor is causing too much resistance. Cycling the A/C off and back on will turn the A/C back on unless the condition still exists or there is something wrong with the compressor RPM sensor.

It is hard for me to imagine that there is no RPM sensor on a modern Toyota A/C compressor. If you have run your hands completely around every surface of the compressor, including the underside and back side without finding any other electrical connections besides the clutch, then the system on your car uses some other method for determining compressor RPM that I am not familiar with. BTW, changing the RPM sensor on the compressor usually requires discharging the system and removal of the compressor.

Check the compressor drive belt to make sure it is not slipping or glazed. If there is more than 30,000 miles on the belt, it wouldn't hurt to change it.

You have mentioned a couple of times that the system is full of 134A. Did you verify this through the sight glass or with gauges or are you assuming this because the system cools when the compressor is engaged? The correct way to verify this is through the sight glass or with gauges. In any event, if refrigerant levels are low, the low pressure switch will keep the clutch from engaging but it will not make the A/C button flash unless the oil that is mixed with the refrigerant is low and the compressor is seizing.

The Chicago area is also expecting a heat wave of sorts - the temps are supposed to reach the 50's this week!

The flashing light on the AC Button means the pressure switch on the high side is shutting the system down. Either the pressure is wrong, or the switch is toast. See an AC specialist if you can't test this stuff yourself.

I once thought that I could service my AC system, and messed it up. All I lost was the time and material to make the mistake; it would have cost the same to do the service had I gone to the shop in the first place.

On every Toyota I am familiar with, the flashing light on the AC button does not have anything to do with the pressure switch; it means that the system has detected a difference in compressor and engine RPM. Does the 95 Corolla have a different system?

Unknown.

I was not aware that the AC had a tach on it. In every instance of a flashing light, it meant there was an issue with pressure. In any case, the AC Technician should know what a flashing light means, and the OP should pay him a visit.

On Toyotas with low refrigerant levels, there is no flashing light.

Hey guys, I've been checking the wiring and found some melted wires on 2 pigtails that plug into the main fuse/relay box. Gotta correct that before going any further. No blown fuses! If this does'nt fix it, I'm going to the dealer. Thanks guys. goldy9955

The DX is a 1.8L with 4spd. The standard model is a 1.6L with 3spd.

I'm pretty sure your combination was never sold new in the North America.