Skip the auto shop - Our mechanics make house calls

P2518 OBD-II Trouble Code: A/C Refrigerant Pressure Sensor “B” Circuit High

check engine light logo

P2518 trouble code definition

A/C Refrigerant Pressure Sensor “B” Circuit High

What the P2518 code means

P2518 is an OBD-II generic code for the engine control module (ECM) detecting the A/C refrigerant pressure sensor B is shorted to reference voltage.

What causes the P2518 code?

  • The ECM got a short circuit signal from the A/C refrigerant pressure sensor B and sets the code in memory.

  • The signal may come through the A/C control module through the network on some vehicles.

What are the symptoms of the P2518 code?

  • The A/C may signal a fault on the control panel for the A/C on some vehicles.
  • The A/C may be disabled on some vehicles depending on manufacturer.
  • The A/C light may flash indicating a problem in the A/C system.

How does a mechanic diagnose the P2518 code?

  • Scans codes and documents the code in the ECM or A/C module

  • Checks the A/C system charge level to make sure it is okay

  • Compares sensor A and sensor B to compare sensors input versus the actual charge level

  • Performs the manufacture pinpoint test on the A/C sensor to verify the failed sensor or wiring

Common mistakes when diagnosing the P2518 code

  • Replacing the sensor without verifying the sensor B reading versus sensor A
  • Failing to clear the ECM or A/C codes after the codes are fixed
  • Replacing parts when the connector is shorted internally

How serious is the P2518 code?

Code P2518 is a code for the A/C system and will only be an uncomfortable situation due the A/C not working on a hot day.

What repairs can fix the P2518 code?

  • Replacing the A/C pressure sensor B
  • Repairing the wiring harness or connector to sensor

Additional comments for consideration regarding the P2518 code

Code P2518 is not very common since most vehicles do not have two pressure sensors in the A/C systems they have and only use one.

Need help with a P2518 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

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

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222 code means The manufacturer specifies a range of acceptable voltage to be produced from the throttle position...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...


Related questions

Q: My car has poor acceleration.

From what you've described, it sounds like you may have a mass airflow sensor that is giving incorrect data for the altitude you are at. This can cause low power, pinging, and O2 codes indicating a too lean condition. A...

Q: Traction and Check Engine Light on

Hey there. Your car is equipped with wheel speed sensors at each of the four wheels which monitor wheel speed while relaying this information constantly to the ABS and traction control system which are controlled by the car's ECU. ...

Q: Trouble running when the engine warms up, dash lights on - 2007 Subaru B9 Tribeca

The P0137/P0157 codes indicate the "rear" (behind the catalytic converters) oxygen sensors are not functioning properly. In turn, they are signaling (incorrectly) for more fuel, which is causing the P0172/P0175 over-rich codes. This is clogging your converters, as well as...