I have a 98 vert and the a/c light is blinking and nothing but hot air is blowing. So, I think it's low on freon. Tryed putting 134a freon in and the system already has freon in it. So, if it already has freon in the system and it's blowing hot air and the a/c light is blinking, what could be causing the light to blink and the unit to blow hot air. (MAYBE A RELAY SWITCH). TKS JOHN

 

It's probably a fuse. When you have the a/c on does the compressor spin at all? If it dosen't, try jumping the pressure switch on the a/c line and see if it starts to spin. If it does, the pressure switch may be bad.

 

I've got the exact same problem. The car was recharged so i know it's full. My god is 134 refrig.is expensive. It's going in on tuesday for an electrical check. The fuses looked OK. I dont know how to test those micro and mini's maybe it's one of them. I hope it's not the compressor. My Honda needed one and it cost 950 bucks. Yikes!!

 

I'm gonna try jumping it 2morrow. I'm hoping it's not my compressor. Also, i'm gonna check fuses. TKS GUYS JOHN

 

SAme problem here... can anyone explain how I check this?

d

 

If the hvac light is blinking, It is throwing a trouble code. The service manual has a list of the codes & how to access the codes. To reset the system you have to disconect the battery.

 

Please read the CODES and post them. You may not have anything wrong with the compressor. It could be the electronic portion of the system (Micropressor). Post the codes here and let us see them. Lets go from there.

The pressure switch is on the high pressure (liquid side) line and is located just inboard of the coolant resovour tank. Look below that area and you can see the AC compressor down low near the bottom of the engine. Make sure that the belt is in place and in good shape. Have someone start the car and turn the air on. Does the compressor energize and turn the center hub??

Please list the codes Here is a good web site to explain what the codes are and how to read them.

This is the absolute best C5 Code web site!!!

http://www.corvettedoctor.com/Codes_Page.htm

Bill Curlee

 

Ok... codes are as such:

RDCM B2263H

RDCM B2265H

BCM 2723H

Funny thing is, there are no HVAC codes. I also checked the obvious (& well identified) A/C & HVAC fuses. All were ok.

hope someone can help

thanks

d

 

BCM 2723 is PASS KEY Detection CKT. Your key resistor pellet was probably dirty OR your Ignition switch contacts are dirty.

2263 & 65 are Door Control Module codes. They deal with the memory position of your mirrios. I would clear them and see if they come back.

Your AC compressor is on the passengers side of the engine way down LOW!! It has it's own belt and tensioner. Look on the bottom front of the engine. It directly below the thermostst housing.

BC

Bill

 

Ok, I located it. How can I tell if compressor is working?

I installed two new serpentine belts, so the belts are fine

thanks again Bill

d

 

With the engine running and AC "OFF" the center hub should NOT be spinning. When the engine is running and you turn the AC to "ON", electromagnets cause a clutch to lock-up and the center hub will start spinning.

Hope that explains it.

BC

 

Hey Bill,

I just tried what you told me, the center hub does NOT spin either way. Besides, the A/C light doesnt stay on, it just blinks a few times, then goes off.

I'd like to test the pressure switch, how do I do this?

thanks again, greatly

D

 

Locate the AC pressure switch. It is on the smaller diameter aluminum pipe next to the coolant resiviour. It is an electrical plug with two wires. The switch will be screwed into the aluminum line. Un-plug the connector and turn the system on (engine running, AC on) Use a paper clip or some small guage wire and jumper the two pins in the wiring harness connector. If the compresor comes on remove the jumper. That will indicate that the switch is bad OR that the system is very low on charge. Get back to me with the results.

 

ok.. getting closer.

I did locate a connector, which had 3 female receptacles in it when I popped it off. This is on the aluminum pipe directly underneath the coolant reservoir. The connector is also screwed into the pipe.

is this the right one? which of the 3 femaule prongs do I jump? or does it matter?

 

Woops,,,,,you will NOT be able to do the jumper test on that plug. Do this. Check the fuses. Under Hood Elsct Center, fuse 16 and Fuse 34.

There are two grounds for the circuit. G-106 and G-102

G-102 is the ground for the Compressor clutch. G-106 is the relay ground.

Micro relay# 34 energizes the clutch for the compressor It is labled A/C CLU. Check all of that and let me know if you find anything.

Here is where all of the grounds are.







See if that helps.

BC

 

having a bit of trouble finding ground nearest motor. :o

Fuses were fine

 

Tryed jumping the comp with a wire-does'nt work/ no codes/ tryed letting some of the freon/pressure off the system-still does'nt work/light still blinks than goes off and blows hot air. Lost at this point. JOHN

 

I think it may be time to get out the test light. Lets make sure that the pressure switch is getting power since we cannot manually jump it. BTW Bill C. is really good at electrical diagnostics. Have confidence that he or someone else on this thread willfigure this out for you. Jer.

 

GOT OUT THE TEST LIGHT AND I HAVE POWER BUT NO A/C. DO YOU KNOW HOW MUCH PRESSURE THE LINES OR SUPPOSE TO HAVE. SOMEONE SAID AROUND 200-230, ANYTHING OVER THAT THE A/C WANT WORK. TKS JOHN

 

That pressure ststement is not totally correct! You need to have the system running and read the LOW SIDE pressure and HIGH SIDE pressure. The low (suction) side should be around 30 PIS and the high (Liquid) side will be around (depending on heat load) 250-300 PSI on a PROPERLY operating system. It is VERY difficult to say what pressure that you should have in the system with it in a NON-RUNNING state. I would guess 65-80 PSI. You will need R-134 Guages because the shrader fittings are not the same as R-12. The low side pressure is more meaningful than the high side when the system is operating.

It is easy for me to grab the book and a volt/Ohm meter and trouble shoot. It is difficult to relay that information to someone on the other end of a monitor. Not that I have not done it in the past. If your willing to probe with a test device and under stand what the meter is telling you, I'm willing to provide info.

This is what you need to do. Unplug the electrical connector on the compressor. With a Volt meter on DCV connect the positive meter lead on the "DARK GREEN" wire contact in the plug and the other end to the BLACK wire contact in the plug. Energize the AC system. You should see +12 VDC. If you have 12 volts DC the compressor should be running. If not the clutch is bad. Check the clutch coil with an OHM Meter and it should read (I'm guessing) around 3-4 ohms. It should NOT read infinite.

Try that and provide the results and we will continue.

BC