P2128 on Chevrolet
Throttle/Pedal Position Sensor E Circuit High Input
P2128 on Chevrolet vehicles indicates throttle/pedal position sensor e circuit high input. Au7o has documented this code across 1 Chevrolet model — most commonly on Avalanche. This code means the throttle or accelerator pedal position sensor 'E' is sending a signal voltage higher than its normal expected range. Modern vehicles use electronic throttle control, where pedal and throttle sensors (often with redundant 'E/F' channels) tell the computer how far the driver is pressing and how far the throttle is open. A high-input reading indicates an electrical fault such as a short to voltage or a wiring problem in that sensor channel. The computer may limit throttle response or enter a reduced-power 'limp' mode for safety until the fault is resolved. Typical repair costs on Chevrolet range from $100 to $500, depending on the specific model and root cause.
Common Causes of P2128
- •Faulty pedal/throttle position sensor (channel E)
- •Wiring shorted to voltage or power
- •Corroded or damaged sensor connector
- •Open or high-resistance ground/reference circuit
- •Chafed or pinched harness wiring
- •Faulty accelerator pedal assembly or throttle body
- •Faulty engine control module (PCM) — rare
P2128 on Chevrolet by Model
Chevrolet Avalanche(1 issue)
- Reduced Engine Power Mode from Throttle Body and Pedal Sensor Faults2007-2013
The 2007-2013 Avalanche frequently enters "Reduced Engine Power" mode, severely limiting acceleration. The most common causes are the electronic throttle body wearing out or the accelerator pedal position sensor (APP sensor) developing faults. The vehicle becomes barely drivable in this mode, struggling to accelerate to highway speeds. The issue can occur intermittently before becoming permanent.
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View P2128 across all makes →Frequently Asked Questions
What does P2128 mean on Chevrolet?▼
P2128 stands for "Throttle/Pedal Position Sensor E Circuit High Input." This code means the throttle or accelerator pedal position sensor 'E' is sending a signal voltage higher than its normal expected range. Modern vehicles use electronic throttle control, where pedal and throttle sensors (often with redundant 'E/F' channels) tell the computer how far the driver is pressing and how far the throttle is open. A high-input reading indicates an electrical fault such as a short to voltage or a wiring problem in that sensor channel. The computer may limit throttle response or enter a reduced-power 'limp' mode for safety until the fault is resolved. On Chevrolet specifically, this code is documented across 1 model.
What causes P2128 on Chevrolet vehicles?▼
Common causes on Chevrolet: Faulty pedal/throttle position sensor (channel E), Wiring shorted to voltage or power, Corroded or damaged sensor connector, Open or high-resistance ground/reference circuit, Chafed or pinched harness wiring. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2128 on a Chevrolet?▼
Repair costs on Chevrolet range from $100 to $500, depending on the specific model and root cause.
Which Chevrolet models have P2128 documented?▼
Au7o has documented P2128 on 1 Chevrolet model: Avalanche.