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OBD II Fault Code P1F21 :

Description of Fault code P1F21

Fuel Cell System Battery Voltage Low

Possible failuer P1F21

  • FCVSCM failure
  • Open-circuit of Battery to DC-DC Converter Cable
  • DC-DC Converter failure

Diagnostic Procedure using AutoHex II Scan Tool

  • The rear average wheel speed > 15km/h and vehicle speed on the meter<1km/h
  • If the rear average wheel speed > 15km/h and VSP<1km/h lasts for 0.3 seconds, the malfunction is determined.

Test Conditions using AutoHex tester

  • Vehicle speed / wheel speed is normal
  • Brake is out of action
  • The automatic brake is out of action

Clear Fault codes Conditions

  • The rear average wheel speed > 15km/h and vehicle speed on the meter<1km/h
  • If the rear average wheel speed > 15km/h and VSP<1km/h lasts for 0.3 seconds, the malfunction is determined.

MIL Status

  • Glow ON

Key learning when all keys lost


Note:

  • AutoHex II is a professional Auto diagnostic.
  • This fault code is a GERENRIC fault code, some cars may change the meaning of this fault code.
    To get the accurate fault code description you may use AutoHex II

More Fault codes:

OBD II Fault Code P1F22
OBD II Fault Code P1F23
OBD II Fault Code P1F24
OBD II Fault Code P1F25
OBD II Fault Code P1F26
OBD II Fault Code P1F27
OBD II Fault Code P1F28
OBD II Fault Code P1F29
OBD II Fault Code P1F2A
OBD II Fault Code P1F2B
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