94 a/c compressor doesnt engage
 

Fans come on, jumped compressor to battery it comes on ice cold air, also checked pressure it was fine. Relay is good. Could this be pressure switch or diode? I need some help

Check the "other" relay right next to the cond fan relay......left/drivers side of the car right by the rad....like between the drivers side headlight and the rad....there are two held on by a small bolt.

I switched them and the fans still came one and compressor didnt

Any other suggestions

I have also checked fuses under dash did see one for ac under hood

Did not find one in fuse box under hood

Have a volt meter/test light...prefer volt meter.

On the AC Compressor relay - KO/EO or OF - blower motor on and ac button on the dash pressed.

BLK/YEL should have 12v.

WHT should have 12v.

RED/BLU should have continuity to ground - volt meter checks for this. If you only have a test light then one end to to WHT wire and the other to the RED/BLU.

Tell us what is missing?

Now I'm going out to check the tire pressures in my cars :)

Red blue has no ground checked with volt meter

Red blue went to compressor rely other two u had me check went to fan relay both had 12v

I have also unplugged pressure switch and jumped the wires did same thing

Ac switch on dash works, turns fans off and on

Then we are missing each other somewhere.

What is the color of the four wires going to the ac compressor relay?

Check whether you have 12V to the red/wht wire to the pressure switch. If not the AC diode may be open.

Check for ground available to the blu/red wire at the AC switch on dash w/ AC switch closed.

Check for continuity across the AC thermostat w/ keyswtich On. An open thermostat would produce your symptoms.

Do you have a wiring diagram to follow? This will help to understand the checks.

good luck

I'm sorry I miss read what u said recheck wires going to compressor relay two had 12v and ground had no continuity

Going to check pressure switch and ac switch now not sure how to check thermos

Unplug pressure switch that is located below battery. The red/wht wire should have 12V with key in II position. The blu/red (I think this is the wire color) should have ground with the a/c turned on and the fan turned on inside the car.

Pressure switch wires were good couldn't get dash out to check ac switch

If the fans come on does that mean the pressure switch is good?