Oxygen Sensor Signal Swapped Bank 1 Sensor 1 / Bank 2 Sensor 1
Table of contents
P0040 MERCURY Possible Causes
- Bank 1 Sensor 1 / Bank 2 Sensor 1 harness is open or shorted
- Bank 1 Sensor 1 / Bank 2 Sensor 1 circuit connectors (wrong connection)
- Faulty Engine Control Module (ECM)
How do I fix code P0040 MERCURY?
Check the “Possible Causes” listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector’s pins.
Cost of diagnosing the P0040 MERCURY code
The cost of diagnosing the P0040 MERCURY code is 1.0 hour of labor. The auto repair labor rates vary by location, your vehicle’s make and model, and even your engine type. Most auto repairs shops charge between $75 and $150 per hour.
Possible Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0040 MERCURY Description
The heated oxygen sensor (HO2S) monitor determines if the HO2S signal response for a fuel shift corresponds to the correct engine bank.