So I got a P0153 code. I removed the driver side sensor and replaced it. I hooked up an ODB scan tool and I got 0 volts for the sensor I changed. See below:



Does anybody have a wiring diagram so I can trace the wires to see if I can find a break?
If you guys have another way to go please let me know. Thanks for the help.

 

1998 Ranger XLT Vin Code X 4.0 eng

 

There are 2 wires for the front DS O2 sensor: orange (signal return) and red/black (signal).

Orange is a dedicated sensor ground from the PCM and it is used for several engine sensors including the other oxygen sensors. The orange O2 wire is spliced to a group of other orange wires inside the harness. Unless it is cut on the short branch to the DS O2 sensor, it is OK.

The red/black signal wire should be checked for open and short to ground - either can cause a 0v reading at the PCM. Disconnect the sensor and the PCM before running continuity checks.

It is a short run for both wires from the sensor directly to the PCM connector. The only intermediate plug connector is the one on the sensor itself.

 

I checked the wiring and it looks ok. I got a ground on the orange wire and I got continuity on the red/black wire to the PCM connector and no short to ground.

Now what?

Could it be that I got a bad O2 sensor?

Is there a way to test the sensor? Maybe I just will return it and get a new one.

 

Any one have any other ideas?

 

If the wiring and connectors are OK, then the only things left are the PCM and the oxygen sensor. Chances of the PCM causing this are just about zero.

 

The new sensor is in and working fine! Guess I got a bad part after all.