Parts for your 2015 Ford Fiesta-Throttle position sensors

2015 Ford Fiesta throttle-position-sensors: what they do and how to look after them

Based on Ford’s Workshop Manual for the Fiesta (Section 303-14: Electronic Engine Controls), Motorcraft service information, and OBD-II diagnostic coverage for the model year, the 2015 Ford Fiesta does use throttle-position-sensors. They’re built into the electronic throttle body as dual, redundant position sensors (often called TPS1/TPS2) and monitored by the PCM. This is part of Ford’s Electronic Throttle Control system, which removes the traditional throttle cable and uses sensors and a motorised throttle plate to manage airflow. Relevant diagnostic trouble codes for this setup include P0121–P0124 and P2135, all of which point to throttle position signal issues documented in Ford service literature.

On a 2015 Fiesta, the throttle-position-sensors are there to tell the engine computer exactly how far the throttle plate is open. Paired with an accelerator pedal position sensor, they let the PCM balance driver demand with smooth engine response, stable idle, and proper fuel and spark. That’s why a flaky signal can trigger limp-home, rough idle, poor acceleration or a glowing check engine light.

Because the sensors are integrated into the throttle body, they’re not a separate, bolt-on item. If the TPS signal fails testing per the Ford diagnostic routine, the fix is typically a complete throttle body replacement. Use a quality part, fit a new gasket where required, and don’t force the throttle plate by hand. After replacement, the Fiesta may need an ETC/throttle relearn or KAM (keep-alive memory) reset. A scan tool procedure is ideal, but many techs in Aus and NZ will also do a battery-off KAM reset followed by an idle learn and a short drive cycle to let the PCM relearn positions.

Servicing under the bonnet is straightforward if done carefully:

• Inspect the throttle body and connector at service intervals for moisture, oil contamination, or chafed wiring.
• If cleaning is needed, use a throttle-body-safe cleaner, avoid harsh sprays on the electronics and never wedge the blade open.
• Check for air leaks at the intake duct and PCV hoses – unmetered air can mimic TPS faults.
• If you see codes like P2135 or correlation faults, follow Ford’s pinpoint tests first, don’t throw parts at it.

Done right, the electronic throttle and its position sensors deliver crisp response, stable idle and consistent fuel economy for hundreds of thousands of kilometres.

Popular questions

Does the 2015 Ford Fiesta have a separate, replaceable TPS?
No. Ford integrates twin throttle-position-sensors into the electronic throttle body. If the TPS is faulty, the remedy is to replace the throttle body assembly and carry out a throttle relearn/KAM reset as specified in Ford service procedures.

What are the tell-tale signs the Fiesta’s TPS/throttle body is on the way out?
Common symptoms include erratic idle, hesitation off the line, sudden limp mode, and the check engine light with codes like P0121–P0124 or P2135. Before replacing anything, check for intake air leaks and connector or wiring issues, as they can trigger similar faults.

Does the throttle body need calibration after replacement?
Yes. The PCM needs to relearn throttle plate positions. A scan tool ETC relearn is best practice. If that’s not available, a KAM reset followed by an idle learn and a gentle drive cycle usually sorts it. Expect the idle to hunt slightly until the relearn finishes.