P2102: Throttle Actuator A Control Motor Circuit Low

P2102 means the output stage for throttle motor A sees a voltage or current that points to a short toward ground or an overloaded driver. GM lists P2100-P2103 together in its 2018 calibration as faults that limit engine power and default the throttle authority; a Bosch-based GM ECM of 2012 assigns its output-stage checks (short circuit, overtemperature or overcurrent, open load) to this group with about 0.1 s detection. Apart from such tables, no maker publicly documents P2102 on its own; many current ECUs report the same fault under P2100 with a failure-type byte. CARB requires circuit faults of output components to be detected. The throttle drops to limp position and power is cut. The high-side counterpart is P2103.

High severity. Can I keep driving?Be careful: the car may suddenly lose power. If it goes into limp mode, get off the highway and calmly make your way to a repair shop.

Symptoms

Limp mode with throttle at fixed opening
Engine warning lamp on
Pedal input largely ignored

Most likely causes

Motor wire chafed through and shorted to ground
Shorted winding or jammed motor drawing excess current
Water in the throttle connector bridging terminals
Faulty throttle driver in the engine control unit

What to check, in order

Start with the simplest. You can tick off each step.

Check the pedal and throttle connectors
With the connector unplugged, check whether the signal wire is making contact with ground.
Use live data to confirm that both sensors rise smoothly and consistently
Clean the throttle if it has carbon buildup
Run the relearn procedure with the scanner if the manufacturer requires it
Replace the part identified by the diagnosis

Good to know

Repair difficulty: medium
It can trigger limp mode.
It affects emissions.

What each character of P2102 means

P: Powertrain: engine and transmission
2: Generic code: same on every make
1: Air and fuel
02: Specific fault in that system

Frequently asked questions

Can I keep driving with code P2102?

Be careful: the car may suddenly lose power. If it goes into limp mode, get off the highway and calmly make your way to a repair shop.

What causes code P2102?

The most common causes are: motor wire chafed through and shorted to ground; shorted winding or jammed motor drawing excess current; water in the throttle connector bridging terminals.

Related codes

Sources

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.