Ford Escape P0122 Trouble Code – Test your TPS
When your 3.0 Duratec engine has a problem with the throttle position sensor, your engine computer will store a DTC and trigger the Ford Escape P0122 check engine light. The throttle body is the unit that controls the amount of air that enters the engine, and it utilizes the throttle position sensor to determine how far the throttle plate has opened. Your Ford Powertrain Control Module ( PCM ) uses this information to control the fuel and spark in your 3.0 liter engine.
The specific verbiage for the Ford Escape P0122 trouble code is Throttle Position Sensor/Switch A Circuit Low Input. The TPS sensor is sending a signal that’s far below what your Ford Escape engine computer is expecting. This means that your three wire throttle position sensor has an issue with the wiring harness, connectivity to the ECU or the sensor is beginning to fail.
Today I’ll be showing you how to fix the P0122 trouble code in your 2007 Ford Escape with a 3.0 liter engine in it. Because your Ford Escape throttle position sensor works on a DC voltage, you will need a digital multimeter to complete this tutorial. Our 2007 Ford SUV will trigger a check engine light when the throttle sensor sends a signal that’s lower than .17 volts of DC power.
Ford Escape P0122 symptoms
- Low idle / surging idle
- inconsistent throttle response
- Engine stalls
- uncontrollable throttle
- CHECK Engine light ON
How to test your Ford Escape Throttle position sensor Signal
Before you begin testing your throttle position sensor, you’ll need to turn your ignition key to the “ON” position. Open your hood and follow your intake piping back to your throttle body in your 3.0 liter engine. You will find the TPS sensor mounted on the opposite side of the throttle blade, and it’s connected by a three pin wiring harness.
You will be testing the signal wire of your 3.0 liter Duratec engine, which in this scenario means PIN B of our 2007 Ford Escape throttle sensor wiring schematic. With the ignition key turned to the “ON” position, you should see between .8-1.0 volts of DC signal with the throttle plate closed.
Now manually open the throttle blade fully open, or have a friend get into your car and press down on the throttle all the way. At this throttle position your sensor should be sending a signal between 4.5 and 5.0 volts of DC power. Remember that these readings won’t be exact in your Ford, but it should be around that voltage.
If you don’t have this voltage at PIN B, check PIN A for a low reference ground signal. The last wire of your 3.0 liter Ford Escape throttle position sensor to test is PIN C which should be a 5 volt power wire.
When your Ford Escape throttle position sensor doesn’t return the voltage specified above, it’s a sign that your throttle position sensor has failed. You will need a replacement Ford Escape throttle position sensor, and will need to calibrate it to show these voltages at the closed position as well as fully wide open.