U3974

U3974 Ford engine fault code diagnosis, code meaning,symptoms and how to fix it.

U3974 Diagnosis

The CHM does not suupport PWM type DRLs. The vehicle has a BHM mismatch with the CHM. Replace the CHM with one that is compatible with the BHM.The BHM is detecting more than one smart switch with the same ID number present on the vehicle. The outputs controlled by the switch and the indicator in the switch are commanded OFF.

The disconnected pipe malfunction is detected when the ventilator tube from the valve cover to the separator device is disconnected resulting in a pressure below the lower limit.Both of these malfunctions will result in a DTC being set.

Ford U3974 Fault Code Meaning :

Ford U3974 Symptoms :

Ford U3974 Reasons :

How To Fix Ford U3974 Trouble Code ?

Which Ford cars have the code U3974?

  • U3974 Ford Aerostar
  • U3974 Ford Bronco
  • U3974 Ford C-Max
  • U3974 Ford C-Max Energi
  • U3974 Ford C-Max Hybrid
  • U3974 Ford Contour
  • U3974 Ford Crown Victoria
  • U3974 Ford EcoSport
  • U3974 Ford Econoline
  • U3974 Ford Edge
  • U3974 Ford Escape
  • U3974 Ford Escape Hybrid
  • U3974 Ford Escort
  • U3974 Ford Everest
  • U3974 Ford Excursion
  • U3974 Ford Expedition
  • U3974 Ford Explorer
  • U3974 Ford Explorer Sport Trac
  • U3974 Ford F-150
  • U3974 Ford F-250
  • U3974 Ford F-350
  • U3974 Ford Fiesta
  • U3974 Ford Flex
  • U3974 Ford Focus
  • U3974 Ford Focus Electric
  • U3974 Ford Freestar
  • U3974 Ford Freestyle
  • U3974 Ford Fusion
  • U3974 Ford Fusion Energi
  • U3974 Ford Fusion Hybrid
  • U3974 Ford Fusion Plug-In Hybrid
  • U3974 Ford GT
  • U3974 Ford Mustang
  • U3974 Ford Mustang Mach-E
  • U3974 Ford Mystique
  • U3974 Ford Probe
  • U3974 Ford Ranger
  • U3974 Ford Taurus
  • U3974 Ford Taurus X
  • U3974 Ford Tempo
  • U3974 Ford Thunderbird
  • U3974 Ford Transit
  • U3974 Ford Transit Connect
  • U3974 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.