P05CE: Cold Start B Camshaft Position Timing Performance Bank 1

What does P05CE mean?

During catalyst heating after a cold start the engine module commands a specific cam phaser position for more residual gas and exhaust heat; CARB requires this to be monitored under codes separate from the normal cam codes. These 'performance' codes are GM's current form (since about 2015/16; older GM engines and Ford use the direction codes P052A ff and P054A ff): fault when commanded and actual position differ by more than 4° or 6° once the target is stable. P05CE watches exhaust camshaft B on bank 1 – the cold-start counterpart of P0014. GM's 2.0 L turbo sets it above 6°, 65 of 75 samples, as type A; 2025 tables list type B. Toyota's T24A-FTS in the 2023–24 Crown and Grand Highlander and Lexus TX 350 set it from overly tight software, fixed by reprogramming the engine module.

The code tells you which monitor failed, not which part is broken. Test before replacing parts.

Symptoms

• Check engine light on (GM mostly after two trips)
• Often no noticeable symptoms, possibly rough cold idle
• Higher cold-start emissions

Common causes

• High Insufficient cold oil supply: wrong viscosity, low level, worn oil
• Medium Oil control valve sticking or screen clogged
• Medium Phaser worn or lock pin not releasing; on electric phasers a damaged phaser motor
• Low Timing chain stretched or skipped
• Low Engine module software

Likelihood is a general estimate across vehicles; your make and model may differ.