Your vehicle’s air conditioning system doesn’t seem to be operating. What could be the problem? There is any number of components and parts involved in the air-conditioning system of any vehicle. One problem, however, could be the A/C clutch relay. You may also hear this referred to as an A/C compressor relay or a compressor clutch relay.
To determine whether or not an A/C clutch relay is faulty, there are couple of methods that can be used. One involves a multimeter.
Let’s look at how to use a multimeter to check your vehicle’s A/C clutch relay. After that, a simple relay switch method will be described, in case you don’t have access to a multimeter.
Do You Have a Bad Relay?
Signs and symptoms that you have a bad relay:
- Your vehicle’s A/C compressor isn’t turning on – It’s normal to notice some type of sound from your compressor clutch when the vehicle’s air conditioning system is turned on. A clicking sound, for example. But the compressor won’t even turn on if there’s a problem with the relay.
- No cool air flow – Granted, no cool air flow could point a to a vast array of issues with your vehicle’s air conditioning system, but a bad A/C clutch relay is one of them.
- Cooling is erratic – If the air conditioner in your vehicle is weak or erratic, the compressor may be receiving a depleted load thanks to a faulty relay.
Your vehicle may have a warning light of some sort to let you know if the A/C system of your vehicle is malfunctioning. In some vehicles, the light flashes when there’s a problem. Not all vehicles are equipped with this, however.
A/C Clutch Relay Check with a Multimeter
Obviously, you’ll need a multimeter for this procedure.
- Remove the relay from the fuse/relay box.
- The multimeter should be in Ohmmeter or Resistance Measurement mode.
- Put the range meter in minimum range if you have a manual ranging multimeter (somewhere on the lines of 200 ohms).
- Connect the multimeter leads across the relay’s coil terminals.
- You should get a reading on the multimeter of 40 to 120 ohms for a normal coil.
- A damaged coil will show out of range and the relay will need to be replaced.
A/C Clutch Relay Check Via Relay Swap
You can test your vehicle’s A/C compressor relay without a multimeter, if you feel comfortable. Replace the clutch relay (in the fuse and relay box) with a similar relay that you know is functional (possibly your horn relay). After that, if the A/C works or the flashing warning light stops flashing, the A/C compressor relay should be replaced.
If automotive repair isn’t in your list of talents, an automotive technician can do it for you relatively inexpensively.
We Carry Automotive A/C Compressor Clutches and Assorted Other Parts
R&Y A/C Compressors has all the parts, components, and kits you need for your vehicle’s AC. Some of the products we offer are:
- Tubes
- Accumulators
- Condensers
- Evaporators
- … and much more
To reach our customer service department, please call 305-919-8864 between 8:30 AM and 5 PM EST, Monday through Friday. (Saturdays, from 8:30 AM to 2:30 PM.) If you’d rather, you can fill out our convenient online form, send it in, and we’ll respond.
You may also choose to send us an email at [email protected]. We look forward to working with you.