Parts for your 2003 Toyota Highlander-Camshaft sensor

2003 Toyota Highlander (Kluger) Camshaft Sensor — What it Does and How to Look After It

Based on Toyota’s factory service information (Toyota Technical Information System service manuals and 2003 Highlander/Kluger wiring diagrams) and the diagnostic section listing DTCs P0340/P0345, the 2003 Toyota Highlander (known as Kluger in Australia and New Zealand), whether fitted with the 2.4L 2AZ-FE inline-four or the 3.0L 1MZ-FE V6, uses one or more camshaft position sensors. So yes — a camshaft sensor is relevant and fitted on this model.

The camshaft sensor (often called CMP) keeps the engine computer in the loop about which stroke each cylinder is on, syncing with the crank sensor to control fuel injection timing, ignition timing, and variable valve timing (VVT-i). On the 2AZ-FE, it lives at the cylinder head and tracks the intake cam. On the 1MZ-FE V6, there are sensors for the cylinder banks so the ECU can accurately manage both sides. Without a clean, consistent signal, the Highlander can struggle to start, run rough, or lose power, and the check engine light will usually jump in with a cam sensor code.

As part of regular servicing, it’s worth giving the CMP area a quick look when the bonnet’s up. Oil weep from the rocker cover or a brittle connector can upset the signal. A gentle wipe of the mating face and a visual on the harness routing helps. The sensor itself isn’t a high-wear item, but age, heat, and oil exposure can take a toll, especially on vehicles with higher kilometres.

Replacement is straightforward for most home mechanics with basic tools, but many will prefer a workshop to confirm the fault with scan data and waveform checks before swapping parts. When replacing, go with quality components that match the OE spec, and don’t forget a new O-ring if applicable. After installation, clear any codes and verify live data shows stable cam/crank correlation.

• Common symptoms of a faulty cam sensor: hard starting, misfire, poor fuel economy, lack of grunt, stalling, and the MIL with codes like P0340/P0345.
• Good practice: check for oil leaks onto the connector, ensure the wiring isn’t chafed, and keep to regular oil services to support reliable VVT operation.
• When to replace: confirmed sensor fault, persistent cam sensor codes after wiring checks, or intermittent cut-outs traced to the CMP signal.

Popular questions

Does a 2003 Toyota Highlander/Kluger actually have a camshaft sensor?
Yes. Both the 2.4L 2AZ-FE and 3.0L 1MZ-FE engines use camshaft position sensing, as shown in Toyota’s factory wiring diagrams and the service manual sections that reference DTCs P0340 and P0345.

Where is the camshaft sensor located on the 2003 Highlander/Kluger?
On the 2AZ-FE four-cylinder, it’s mounted at the cylinder head near the intake cam. On the 1MZ-FE V6, there are sensors for the cylinder banks near the camshaft ends. Access varies slightly by engine and bank, removing the engine cover and working from the top usually does the trick.

Is it safe to keep driving with a faulty camshaft sensor?
It might still run, but it can stumble, lose performance, and chew more fuel. Prolonged driving can risk catalyst damage if misfires occur. Best bet: diagnose promptly and repair before a minor drama turns into a bigger bill.