OBD-II reference

All 9.533 generic OBD-II codes, explained in detail.

Causes, inspection steps and sources — a comprehensive DIY archive. Created and maintained with love for the detail. Good luck and have fun!

Powertrain generic / SAE

P2517

A/C Refrigerant Pressure Sensor B Circuit Low

A/C refrigerant pressure sensor B signal voltage reads below the lower limit. Either a short to ground in the signal wire, an open reference voltage at the sensor, or an internal short. The ECM ignores the reading and disables A/C closed-loop control until the circuit recovers.

SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number5 / 17

Possible causes

  • Signal wire shorted to ground high
  • Missing 5 V reference at the sensor medium
  • Connector pins corroded - high contact resistance low

Inspection / repair

  • Difficulty: medium
  • DIY: possible
  • Estimated cost: 80–400 €
  • Estimated time: 0.4–1.5 h
  • Component: ac pressure sensor b
  • Component: sensor wiring
  • MIL / check engine light

Sources

References

How to read OBD-II codes

The first letter names the vehicle system, the second digit distinguishes generic from manufacturer-specific, the remaining digits group fault area and number.

PPowertrain: engine, transmission, emissions
BBody: chassis trim, comfort, interior
CChassis: suspension, brakes, steering
UNetwork: CAN, control modules, communication