Parts for your 2015 Toyota Prius-Camshaft sensor

2015 Toyota Prius Camshaft Sensor — What It Does and When to Replace It

Based on Toyota’s technical literature for the ZVW30 Prius — including the New Car Features manual, the Electrical Wiring Diagram, and the Toyota Electronic Parts Catalogue — the 2015 Toyota Prius (2ZR-FXE engine) is fitted with a camshaft position sensor. Toyota identifies it as the “G” or “G2” cam signal, working alongside the crankshaft sensor (“NE”) to keep timing and fuel delivery spot on.

This camshaft sensor lets the engine control module know exactly where the intake cam is. That matters for quick hybrid starts, smooth hand‑offs between EV and engine, accurate sequential fuel injection, and proper VVT-i operation. If the signal’s off, the Prius can take longer to go to READY, run rough when the engine kicks in, or log faults like P0340/P0341.

There’s no routine maintenance called for, as it’s a solid‑state Hall sensor. Still, during servicing it’s smart to:

• Visually check the connector and loom near the cam cover for oil intrusion, brittle insulation, or damaged clips.
• Confirm there are no oil leaks at the timing cover that could seep into the plug.
• Use the correct oil grade to keep VVT-i happy and prevent timing irregularities that can mimic sensor faults.

Replacement is straightforward under the bonnet. The sensor sits on the cylinder head near the intake cam. For safety on a hybrid, make sure the car is OFF (not in READY), remove the key, and disconnect the 12‑volt negative terminal before unplugging the sensor. Swap the unit, fit a new O‑ring, lightly oil the seal, and refit the hold‑down bolt to factory spec. No special programming is typically required, the ECU will relearn after a few drive cycles. Clear codes and check live data to confirm clean cam/crank synchronisation.

Common signs it’s time to investigate include:

• Check engine light with P0340/P0341
• Long crank or no‑start to READY
• Rough idle when the engine starts, poor fuel economy, or flat performance

Sticking with a quality, correct‑fit sensor for the 2ZR‑FXE by VIN is the go. While some engines can fudge it on the crank signal alone, the Prius is far happier — and more efficient — with a healthy cam signal.

Where is the camshaft sensor on a 2015 Prius?

It’s mounted on the cylinder head by the intake cam, under the plastic engine cover. Look for a small, two‑pin sensor with a single hold‑down bolt and an O‑ring seal. Access is from the top of the engine bay, so there’s no need to get under the car.

Can a faulty camshaft sensor stop a Prius from going to READY?

Yes, it can. The hybrid ECU expects a clean cam signal to sync fuel injection and VVT-i during start. A failed or noisy signal often triggers P0340/P0341, lengthens crank time, or prevents READY. Fixing wiring issues or replacing the sensor usually restores normal starts.

Is cleaning the camshaft sensor worth a try?

If the connector is oily or the sensor tip has metal fuzz, a careful clean can help. However, internal electronic faults won’t be fixed by cleaning. If codes return after a clean and connector check, replacement is typically the reliable cure.