Ford Fault Code
Free · no signupP2237
Check Engine Light / Increased Fuel Burn
Variant 1
System
Emissions
Symptom
Check Engine Light / Increased Fuel Burn
Diagnosis & fix steps
LOGIC: O2 Sensor Positive Current Control Circuit / Open (Bank 1 Sensor 1).
ACTION: Check for broken or melted wiring harness leads near the exhaust manifold. Measure internal resistance of the oxygen sensor's heating element circuit.
Red Seal field insights
Sensor Physics: Wideband air/fuel ratio sensors rely on a precise pumping current to determine oxygen concentration; an open circuit stops all fuel control fine-tuning.
Variant 2
System
Emissions
Symptom
Check Engine Light / Increased Fuel Burn
Diagnosis & fix steps
LOGIC: O2 Sensor Positive Current Control Circuit / Open (Bank 1 Sensor 1).
ACTION: Check for broken or melted wiring harness leads near the exhaust manifold. Measure internal resistance of the oxygen sensor's heating element circuit.
Red Seal field insights
Sensor Physics: Wideband air/fuel ratio sensors rely on a precise pumping current to determine oxygen concentration; an open circuit stops all fuel control fine-tuning.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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