1984 crossfire no power to high pressure switch or compressor clutch??
Forum: C4 HVAC, Fuel, Emissions, and Exhaust
6 Messages
Page 1 of 1
Sponsored Content
I just picked up a crossfire with 87k and manual transmission. Most of the gadgets work fine but a/c. Hvac fan blows on all speeds. When selecting a/c max there's no power to compressor or high pressure switch. Low side switch has power. A/c fuse is good. Cooling fan relay works. Any help would be greatly appreciated thx!
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
SPONSOR AD:: (Our Sponsors help support Vette Registry)
B
Free Member
Moderator
Send PMModerator
Joined: 3/20/2009
Posts: 690
Vette(s): Black 1979 L-82
Black 1996 LT1
Black 1999 Coupe
Start tracing power from the A/C "ON" switch is all you can do.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
That's a perfect description of a Low Refrigerant condition. You need gauges to fill the system properly, but you can confirm my suspicion by removing the plug from the low pressure switch, then putting a jumper wire across the two contacts in the low pressure switch connector. Ignition on, a/c on, but engine does not need to be running. You should hear the compressor clutch activate!
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
Lifetime Member
Moderator
Send PMModerator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 22714
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Hot Rod Roy said:
That's a perfect description of a Low Refrigerant condition. You need gauges to fill the system properly, but you can confirm my suspicion by removing the plug from the low pressure switch, then putting a jumper wire across the two contacts in the low pressure switch connector. Ignition on, a/c on, but engine does not need to be running. You should hear the compressor clutch activate!
I agree....
Joel Adams
C3VR Lifetime Member #56 
My Link 
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
I have tried jumping the low pressure switch. Still no luck with power to the compressor clutch.
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
You said you have power to the low pressure switch. When you jump the low pressure switch, you should have power to your high pressure safety cut-off switch. Do you?
If you have power to your high pressure safety switch, you should have power to your compressor clutch connector. Do you?
If you have power to your compressor connector and your clutch does not actuate, do you have a good ground connection to the other contact in the compressor clutch connector. Do you?
Since you said you have power to your low pressure switch, you should be able to easily see where you have the problem. It's a really simple circuit. Do you have a broken connection somewhere? The wire from the low pressure switch does take a long path around the bottom of the engine on its way to the high pressure safety switch!
Be the first to like this post
Sign In to Like this post
Sign In to Like this post
in Forum: C4 HVAC, Fuel, Emissions, and Exhaust
Sponsored Content