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

More related articles

Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...
P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...


Related questions

Q: Codes P2106 and P0720

Hi, thanks for writing in. Code P0720 is for the output speed sensor for the transmission, and code P2016 is for the throttle control actuator in failure mode and may be due to the transmission codes. The system will need...

Q: My problem is Check Engine Light on. Cruise control does not work, loses power on hills, as if it does not want to pull hill.

Hi there. From the description you have provided, there is several possibilities for your vehicle's drivability problems. Your vehicle's Check Engine Light may help diagnose the lack of power and inoperative cruise control. Accessing the vehicle's computer for codes stored,...

Q: ECU and related components

Your ECU would have to be programmed. Although it is possible nowadays for consumers to download the software from the OEM for a fee, you need an interface cable and knowledge of the programming steps. Once you add up the...