P1129 MERCURY - Downstream Oxygen Sensors Swapped from Bank to Bank
P1129 MERCURY Possible Causes
Crossed HO2S harness connectors (downstream)
Crossed HO2S wiring at the harness connectors (downstream)
Crossed HO2S wiring at the 104-pin harness connectors (downstream)
How is the P1129 MERCURY code repair?Start by checking 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.
What is the cost to diagnose the P1129 MERCURY code
Labor: 1.0The cost to diagnose the P1129 MERCURY code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.
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- Engine Light ON (or Service Engine Soon Warning Light)
P1129 MERCURY MeaningThe heated oxygen sensor (HO2S) monitor determines if the HO2S signal response for a fuel shift corresponds to the correct engine bank. The test fails when a response from the HO2S being tested is not indicated.
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