Powertrain, generic (extended)

P2A48 Alternative Fuel Tank C Pressure Sensor Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

With P2A48 the voltage from the tank C pressure sensor has fallen beneath the lowest value a working sensor ever outputs, even with the cylinder empty. In such three-wire circuits a low reading points to the signal line touching ground, a dead 5 V supply or a short inside the transducer. The gas conversion specialist TransEco attributes its tank A Low code to a sensor shorted to ground and lets the AFCM continue with a fixed 3600 psi substitute while the lamp is on. For the driver, tank C looks drained: the gauge may sink and the module may skip that cylinder although it is still full. No manufacturer documents P2A48 itself. If the reference wire also feeds other sensors, a short elsewhere on it can trigger this code.

Likely causes

Signal wire of the tank C sensor touching ground
5 V reference open or shorted by another sensor on the same line
Internal short in the tank C transducer

Symptoms

  • Check engine light
  • Tank C reported empty despite being filled
  • Less gas range than expected

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–700
Time1–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

alt fuel tank c pressure sensorwiring harnessafcm

Related codes

P2A46P2A49P2A47P2A43P01A0

References: law.cornell.edu, http:.