P0340 Toyota Highlander
Camshaft Position Sensor Circuit Malfunction (Bank 1) · Powertrain Code · High · Repair: Moderate
What is P0340?
The camshaft position sensor on bank 1 is not providing a valid signal. Engine may not start or run poorly.
When the Toyota Highlander triggers code P0340 (camshaft position sensor circuit malfunction (bank 1)), it typically points to an issue in the powertrain system. This is a high severity code, so address it promptly to avoid further damage or safety concerns. Below you'll find the most common causes, symptoms, and repair options specific to the Toyota Highlander.
This repair is rated moderate, meaning some experience and specialty tools required.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Toyota Highlander.
Common Causes on Toyota Highlander
- Camshaft position sensor (CMP) circuit malfunction — sensor or wiring failure
- CMP sensor contaminated with oil from leaking valve cover gasket
- Stretched timing chain causing erratic CMP signal relative to CKP
- Failed CMP sensor due to age and heat cycling
Symptoms
- Check Engine Light on
- Hard starting or extended cranking before start
- Rough idle and possible stalling
- Reduced power and poor throttle response
- May see companion VVT-i codes (P0010-P0014)
Notes for Toyota Highlander
On Toyota VVT-i engines, P0340 often appears alongside VVT codes — replace the CMP sensor first as it is cheaper and easier before investigating timing chain wear.