Ac relay is a relay which respond to ac signal only.when there is no supply given to this relays coil,it wont function.it will change its n/o contact to n/c contact if there is a supply given to its coil.this is the simple exlanation for ac relays.
AC and fuel pump are the same relay
To check the fan relays on the 99 Malibu, you can swap the relay between the AC blower and the fan.
in the engine bay right behind the battery
Alternating Current as opposed to DC Direct Current
If you look carefully, there are 5 or 6 relays. Fuel pump, B-Latch, AC, Air Stepper Motor, O2 heater and Starter relays.
In the relay box next to all the other relays.
Under the hood, on the firewall, far to the drivers side. If you have ac there may be two relays there, the other one is for the ac compressor.
The relay is probably sticking. Go to where all of the relays are and start unplugging relays until it quits.
Check under the air filter housing for the PCM (power control module) if you could open it you would see about 5 relays on a circuit board one of the relays is for ac compressor. In general change the PCM.
I have a 1993 olds cutlass ciera and the AC fan relay is the one in the middle on my car.
Your a/c unit uses different relays(switches) that are energized when the thermostat calls for A/C.
1992 Pontiac grand am ac relay locationi found the relays. they are in the center of the firewall next to the blower case. they are in a case with cover that is bolted to the firewall.