Parts for your 2005 Toyota Echo|yaris-Throttle position sensors

2005 Toyota Echo/Yaris throttle-position-sensors (TPS): what they do and how to look after them

Referencing Toyota’s own technical literature, the 2005 Toyota Echo/Yaris (NCP10/NCP12 with 1NZ‑FE or 2NZ‑FE) is fitted with throttle-position-sensors. The Toyota Repair Manual and New Car Features for ETCS‑i (Electronic Throttle Control System‑intelligent) specify dual throttle position signals built into the electronic throttle body, and the ECM monitors them alongside the accelerator pedal sensor. Toyota’s diagnostic programme lists relevant DTCs (P0120, P0121, P0122, P0123, P0124, P2135) for throttle/pedal position circuits, and the Toyota Electronic Parts Catalogue shows the TPS integrated with the throttle body assembly. So yes—on a 2005 Echo/Yaris, TPS is present, active and important.

On this model, the throttle-position-sensors tell the engine computer exactly how far the throttle plate is open. Because the 1NZ‑FE/2NZ‑FE uses ETCS‑i, the throttle blade is driven by an electric motor rather than a cable, and the TPS pair (redundant tracks for safety) feeds back position so the ECM can nail smooth idle, tidy shifts, good fuel economy and crisp response. When the sensors drift or go out of range, owners may see an idle that hunts, lazy throttle response, higher fuel use, or a check engine lamp with the codes above.

Servicing is straightforward. The TPS on most 2005 Echo/Yaris variants is built into the throttle body, so it’s not a separate bolt‑on piece. If testing confirms a faulty signal, the correct repair is usually a complete throttle body replacement. Before going that far, a careful clean of the throttle bore and plate can help sticky or slow return behaviour. Use a sensor‑safe throttle body cleaner, keep sprays away from the motor housing and connector, and don’t force the blade by hand. After any clean or replacement, allow the ECM to relearn idle (a short drive cycle or an idle learn via scan tool does the trick).

Good practice for a Kiwi or Aussie Echo/Yaris is to inspect the throttle body and air tract around every 20,000–40,000 kilometres, especially if most driving is stop‑start or in dusty conditions. Look for oil vapour build‑up from the PCV system, check the loom and connector for chafing or corrosion, and verify live data for the two throttle position signals with a scan tool—they should track smoothly and agree with each other. If replacing the throttle body, use a fresh gasket, tighten the fasteners evenly, and clear adaptations with a capable scan tool. It’s a tidy afternoon job for a competent home mechanic with a basic socket set, but anyone unsure should book it with a workshop that knows Toyota ETCS‑i.

Popular questions about 2005 Toyota Echo/Yaris throttle-position-sensors

Does a 2005 Echo/Yaris have a separate TPS I can replace?
Most 2005 models here run an electronic throttle body with the TPS built in, so you replace the whole throttle body if the sensor fails. Some earlier cable‑throttle variants exist in other markets, but local 2005 cars typically use ETCS‑i with an integrated sensor.

What are the common signs the TPS is playing up?
Drivers usually notice a check engine light and codes like P0121 or P2135, a rough or wandering idle, flat spots on acceleration, or poor fuel economy. On scan data, the two throttle position signals won’t track smoothly or won’t agree with each other through the pedal sweep.

Can cleaning fix a TPS fault on a 2005 Echo/Yaris?
Cleaning can help if the issue is sticky airflow around the throttle plate rather than an electrical fault. Use throttle body cleaner sparingly and keep it off the actuator and connector. If DTCs persist or the signals are erratic, plan on replacing the throttle body assembly and performing an idle relearn.