Mechanics

MIL LIGHT, P0054 CODE, HELP?!

2005 Ford Focus • 140,000 miles

The MIL light is on, after being given the 54 code, and advice to replace the sensor, we replaced the downstream sensor with an OEM part. The light still comes back on after only a few miles. After re-checking with an OBD scanner, we're getting the same code, but now are being told it's something between the sensor and the computer. Not the actual sensor itself. The fuses are fine, the lower sensor is new and fine, what would be the next logical thing to check to get this darn light to stay off? My daughter just bought this car and can't get it registered without emissions. (Will they even check emissions with the light on?) Any help is appreciated.
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Shelly369
February 26, 2012.




P0054 FORD - HO2S Heater Resistance Bank 1 Sensor 2 Could be an open or short oxygen sensor harness or poor connection. You will fail the emission testing with the CEL being on-

Tiny
Rasmataz
Feb 27, 2012.
Thx. I know it will fail emissions, I'm just trying to figure out the next step. The connections to both sensors seem to be fine, I'm wondering if maybe one of the wires in the upstream (the one not replaced) might be loose inside the harness. Also, do you know anything about the relays? We haven't checked to see if they're all good or not, but 12, 13 1nd 14 aren't even in the box, are they unused or should they be there?
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Tiny
Shelly369
Feb 28, 2012.

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