Exhaust Not Warm Enough Downstream O2 Sensor Not Tested
Table of contents
P1127 MERCURY Possible Causes
- Faulty O2 Sensor Heaters
- O2 Sensor Heaters harness is open or shorted
- O2 Sensor Heaters circuit poor electrical connection
How do I fix code P1127 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 P1127 MERCURY code
The cost of diagnosing the P1127 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)
P1127 MERCURY Description
The heated oxygen sensor (HO2S) monitor uses an exhaust temperature model to determine when the HO2S heaters are cycled ON. The test fails when the inferred exhaust temperature is below a minimum calibrated value.