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P151C Code - A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible

- Code Popularity: 3,261 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC P151C?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Low refrigerant
  • Faulty Low Side Pressure Sensor
  • Low Side Pressure Sensor harness is open or shorted
  • Low Side Pressure Sensor circuit poor electrical connection
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How to Fix the DTC P151C?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P151C code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code P151C Description

The Hybrid Powertrain control module (HPCM2) monitors the low side refrigerant pressure through the A/C refrigerant pressure sensor. The HPCM2 supplies a 5 V reference and a low reference to the sensor. Changes in the A/C refrigerant pressure cause the sensor signal to the HPCM2 to vary. When the pressure is high, the signal voltage is high. When the pressure is low, the signal voltage is low. When pressure is too high or too low, the HPCM2 will not allow the activation of the A/C compressor.
To make the P151C Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Not Plausible DTC evaluation, the HPCM2 compares the A/C Low Side Refrigerant Pressure Sensor reading with the A/C high side refrigerant pressure reading after a dormant soak period.
In addition, to make the P151C Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor Not Plausible DTC evaluation, the HPCM2 also uses the A/C temperature sensor 2 reading.
These two sensors are both in the same environment. The HPCM2 compares the values of these sensors after a dormant soak period. The HPCM2 takes the temperature value and calculates an equivalent pressure for gaseous R134a at that temperature and at the pressure as reported by the Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor and compares these.
DTC P151C sets if both of these comparisons show that the A/C Low Side Refrigerant Pressor Sensor is not in agreement with the other sensors.
To make the DTC P2516 Air Conditioning (A/C) Low Side Refrigerant Pressure Sensor evaluation, the HPCM2 looks for a drop in the pressure value after the compressor has run for a short period after a dormant soak period.
OBDII Code P151C - A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible - AutoCodes.com
P151C Code - A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible

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Information for Specific Makes

  • P151C Buick A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible
  • P151C Cadillac A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible
  • P151C Chevrolet A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible
  • P151C GMC A/C Conditioning Low Side Refrigerant Pressure Sensor Not Plausible

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Code P151C comments

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