Error P04B1 on Foton все модели
Refueling Vapor Control Valve Circuit Low
Code
P04B1
Vehicle
Foton все модели
Category
Powertrain
Severity
✅ LowSymptoms
- Check Engine Light Is On
- Strong smell of gasoline during and after refueling
- Fuel vapor escapes through the tank neck when refueling.
- Unstable priming gun (gun may fire too often)
- Possible increase in pressure in the fuel tank
- Deterioration of the vehicle's environmental performance
Causes
- Broken wire in the valve control circuit
- Oxidized or poorly connected valve connector
- Faulty valve solenoid (winding break)
- Damage to wiring caused by fuel or moisture
- Blown control circuit fuse
- Malfunctioning EVAP control module or ECU (rare)
How to Fix
- Check the fuses of the EVAP circuit and the vapor control valve when refueling.
- Find the location of the valve (usually near the fuel tank or neck)
- Inspect the valve connector: oxidation, deformation, reliability of fixation
- Measure the resistance of the valve solenoid (normal: 20–60 ohms)
- Check the supply voltage and signal wire upon control command
- Inspect the wiring harness from the ECU to the valve for damage.
- Replace the valve if the solenoid is internally broken
- After replacement, check the EVAP system and reset the codes