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94, xjs 6.0, v12, coupe FF44 code

equiprx

Luke Skywalker
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I just replaced the O2 sensors and the code keeps coming
back. There is some reference to a 'heated O2 sensor relay'
in the literature but I don't see the location on the relay
location diagram. Anyone out there have a clue?
 
After installing four 'super' ground straps around the car as indicated in the recall instructions' the code came back within about 10 miles. The only other thing I can think of is a possible cruddy connector somewhere under the car. Any and all advise is welcome, please help!!!!!!!!!!
 
Ok, this is what I have available at the moment. FF44 indicates O2 sensor A bank. I can find nothing about a heater relay in the model year 94 update book, but it is possible that another relay also does that. I have not dug out the wiring diagram book yet. So, at the sensor connectors, compare the voltage of A and
B bank sensors. Heater voltage and grounds should be the same, or close anyway. The o2 output should oscillate (I think) around .5 to 1.5V. Again, the ultimate number dosen't really matter, but that both are behaving approximately the same does. If the A bank sensor is not switching, then look for the cause. Vacuum leaks, stuck injector, Marelli meltdown, etc. You could switch the sensors side to side to see if you got a bad part. If the trouble follows the sensor it will set FF45 Check that the signal from the sensor is actually getting to the ECU The injection ECU is in the right footwell. Pin 6 is the O2 for A bank 23 is the O2 ground, and pin 24 is the B bank sensor. Hope this helps for a start anyway.
 
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