Ford Ecosport P0157: Oxygen Sensor Low Voltage (Bank 2 -Sensor 2)

P0157 is a common OBDII code that occurs in the Ford Ecosport, it’s a general code (this means that it has the same meaning for any vehicle).

This code typically indicates that there is an issue with the wiring or harness going to the sensor, or the sensor itself is bad.  There are other things that cause P0157 to populate.  We’ll cover those below.

  • Bank 2 refers to the side of the engine with Cylinder 2 in the firing order
  • Sensor 2 is downstream of the catalytic converter.

 

Ford Ecosport P0157 Symptoms

P0157 Ford EcosportP0157 Causes: Ford Ecosport

Here are the most common issues that cause the P0157 code in the Ford Ecosport. They are presented in order (somewhat) of most to least likely to cause the problem.

 

 

Ecosport P0157 Diagnosis

Here is a fantastic video that covers all aspects of diagnosing the P0157 code:

 

 

It is possible to diagnose the P0157 with a multimeter. If you use the multimeter, you’ll know whether or not the voltage coming to and from the oxygen sensor is within spec, this can help you determine if it’s your Ecosport’s O2 sensor, or wiring harness that’s the issue.

If you don’t have access to a multimeter, it certainly wouldn’t hurt to check the wiring to between the fuse box and the Oxygen sensor first. If it ends up being a wiring issue, it’ll save you money over buying an unnecessary O2 sensor.

You can also use a voltage test light to determine whether or not the oxygen sensor is getting any voltage at all (they’re about $5 at Walmart). If it’s not getting any voltage, attach the test light to the harness plug and shake the wiring a little bit. If the light comes on, even for a second, you know that you have a short circuit causing the P0157 trouble code.

 

Conclusion

Good luck finding whatever caused P0157 in your Ford Ecosport. If you have anything that you would like to add, please feel free to leave a comment below.