When your 2022 Toyota Camry's gas pedal stops responding, it's not just frustrating—it's dangerous. Code P2138 indicates a throttle position sensor D/E voltage correlation error in the electronic throttle control system, which Toyota calls ETCS-i.
Understanding the Unresponsive Accelerator
The 2022 Camry uses a drive-by-wire throttle system with dual accelerator pedal position sensors (APP sensors) for redundancy. When these sensors send conflicting signals to the ECM, the system enters a protective mode that limits or eliminates throttle response. This is a designed safety feature to prevent unintended acceleration.
What Triggers P2138 in the Camry
The most common causes of gas pedal non-response include: a failing accelerator pedal position sensor assembly, corroded connector pins at the APP sensor, damaged wiring harness between the pedal and ECM, or water intrusion into the footwell area affecting electrical connections. Some owners report issues after floor mat interference, though Toyota's improved pedal design makes this less common.
Symptoms Beyond the Dead Pedal
Before complete pedal failure, you might notice intermittent throttle response, a slight delay when pressing the gas, the engine stuck at idle despite pedal input, or the check engine light accompanied by reduced power mode. The car may also enter limp mode, limiting speed to protect the drivetrain.
Diagnostic Steps
Professional diagnosis involves monitoring live APP sensor data with a scan tool to check for voltage correlation between sensors D and E. The sensors should track together within a specified range. Your technician will also inspect the pedal assembly connector for green corrosion and test the wiring harness for opens or shorts.
The Repair Solution
Most P2138 cases require replacing the accelerator pedal assembly, which includes the integrated APP sensors. This is a relatively straightforward repair, though the part is dealer-only for this model year. Some cases resolve with connector cleaning or wiring repair. After replacement, the throttle system requires relearning through an initialization procedure.