Skip the auto shop - Our mechanics make house calls

How to Replace an AC Evaporator Sensor

evaporator sensor

An air conditioning pressure evaporator sensor changes its internal resistance in relation to evaporator temperature. This information is used by the electronic control unit (ECU) for compressor control.

By cycling the compressor clutch on and off in response to evaporator temperature, the ECU prevents the evaporator from freezing up. This keeps the A/C system functioning properly and prevents damage.

Part 1 of 3: Locate the evaporator sensor

In order to safely and efficiently replace your evaporator sensor you need a couple of basic tools:

locating the evaporator sensor

Step 1: Locate the evaporator sensor. The evaporator sensor will either be mounted to the evaporator or the evaporator case.

The exact location of the evaporator varies from vehicle to vehicle, but it is generally located inside or underneath the dash. Consult the repair guide for your vehicle to determine the exact location.

Part 2 of 3: Remove the evaporator sensor

disconnecting the negative battery cable

Step 1: Disconnect the negative battery cable. Disconnect the negative battery cable with a wrench of ratchet. Then set it aside.

removing the evap sensor connector

Step 2: Remove the sensor electrical connector.

unscrewing the switch

Step 3: Remove the sensor. Apply downward pressure on the sensor to release the tab for removal. You may also need to turn the sensor counterclockwise.

  • Note: Some evaporator temperature sensors require the evaporator core be removed for replacement.

Part 3 of 3: Install the evaporator temperature sensor

installing the new evaporator temp sensor

Step 1: Install the new evaporator temperature sensor. Insert the new evaporator temperature sensor by pushing down on it and turning it clockwise if needed.

reinstalling the electrical connector

Step 2: Reinstall the electrical connector.

Step 3: Reinstall the negative battery cable. Reinstall the negative battery cable and tighten it.

turning on the ac

Step 4: Test the A/C. Once everything is complete, turn on the A/C to see if it’s working.

If not, you should have your A/C system diagnosed by a trained professional.

If you’d rather have someone tackle the job for you, the team at YourMechanic offers expert evaporator temperature sensor replacement.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

Veteran and Military Driver Laws and Benefits in Idaho
The state of Idaho offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch in the...
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP)...
P0477 OBD-II Trouble Code: Exhaust Pressure Control Valve Low
P0477 code means that the PCM has detected an abnormally low voltage reading often due to the exhaust back pressure control valve circuit.


Related questions

Q: Why won't my car go in reverse?

Hello - hopefully the few days where the transmission was losing fluid badly did not damage anything. Causes of "no reverse" include: valve body wear, especially the pressure regulator valve, a loose nut on the transmission main shaft (causes an...

Q: Car starts, dashboard lights flicker, air conditioning shuts off

Hello there, thank you for asking about your 1993 Isuzu Pickup. It sounds like a bad ground in the instrument panel circuit. Looking at the wiring diagram, I see the AC heater control panel and instrument cluster share the same...

Q: My all wheel drive light keep going on and off. My abs light stays on.

There could be a wheel speed sensor that could have failed and is not functioning properly that is causing the ABS and AWD lights to come on. The AWD light will come on in the event that the transmission is...