C3999

C3999 Ford engine fault code diagnosis, code meaning,symptoms and how to fix it.

C3999 Diagnosis

The axle lift 2 output circuit is commanded OFF, but air pressure is detected at the pressure feedback switch. Troubleshoot for axle lift 2 air solenoid fault, and for air pressure switch short circuit fault.The BHM supplies battery power on this circuit when the key is in the RUN or CRANK positions. Troubleshoot for a wiring fault shorting this circuit to ground or for too many optional circuits spliced into it that is causing the BHM to turn it off.

The suspension proportioning output circuit is commanded OFF, but air pressure is detected at the pressure feedback switch. Troubleshoot for suspension proportioning air solenoid fault, and for air pressure switch short circuit fault.

Ford C3999 Fault Code Meaning :

Ford C3999 Symptoms :

Ford C3999 Reasons :

How To Fix Ford C3999 Trouble Code ?

Which Ford cars have the code C3999?

  • C3999 Ford Aerostar
  • C3999 Ford Bronco
  • C3999 Ford C-Max
  • C3999 Ford C-Max Energi
  • C3999 Ford C-Max Hybrid
  • C3999 Ford Contour
  • C3999 Ford Crown Victoria
  • C3999 Ford EcoSport
  • C3999 Ford Econoline
  • C3999 Ford Edge
  • C3999 Ford Escape
  • C3999 Ford Escape Hybrid
  • C3999 Ford Escort
  • C3999 Ford Everest
  • C3999 Ford Excursion
  • C3999 Ford Expedition
  • C3999 Ford Explorer
  • C3999 Ford Explorer Sport Trac
  • C3999 Ford F-150
  • C3999 Ford F-250
  • C3999 Ford F-350
  • C3999 Ford Fiesta
  • C3999 Ford Flex
  • C3999 Ford Focus
  • C3999 Ford Focus Electric
  • C3999 Ford Freestar
  • C3999 Ford Freestyle
  • C3999 Ford Fusion
  • C3999 Ford Fusion Energi
  • C3999 Ford Fusion Hybrid
  • C3999 Ford Fusion Plug-In Hybrid
  • C3999 Ford GT
  • C3999 Ford Mustang
  • C3999 Ford Mustang Mach-E
  • C3999 Ford Mystique
  • C3999 Ford Probe
  • C3999 Ford Ranger
  • C3999 Ford Taurus
  • C3999 Ford Taurus X
  • C3999 Ford Tempo
  • C3999 Ford Thunderbird
  • C3999 Ford Transit
  • C3999 Ford Transit Connect
  • C3999 Ford Windstar

A code is a fault code and it indicates that something has gone wrong with your car's engine.

It can be caused by many different problems, including a faulty battery, a bad fuel pump, or even a cracked exhaust manifold.

You will need to diagnose the problem before you can fix it. The best way to do this is with an OBD scanner tool.

A scan tool will tell you what needs fixing and how much it will cost in order to fix that particular issue.