Fault in the throttle position sensor or its circuit giving a high or incorrect signal; Damaged, chafed or shorted wiring in the throttle position PWM signal line, for example shorted to voltage; Corroded, loose or pushed-out pins in the sensor or control module connectors; Poor or missing ground or reference supply affecting the throttle position signal; Throttle body fault or sticking throttle affecting the position reading; Fault in the engine or transmission control module generating or interpreting the PWM signal; Outdated control module software where a known fault is documented for that model.

P1892

Throttle Position Sensor PWM Signal High.

Buick
Powertrain
Manufacturer code
Medium severity

How this code is built

P: SystemPowertrain
1: Defined byThe manufacturer
8: AreaTransmission
92: FaultThe specific fault in that area

What it means

P1892 on a Buick is a GM-specific code meaning the Throttle Position Sensor PWM Signal is reading high. The throttle position information is passed between modules as a pulse width modulated signal, commonly from the engine control module to the transmission control module on applications that use it. The receiving control unit saw the PWM duty cycle above the expected range, or stuck high, so it set the code.

Symptoms

Check engine light or service vehicle soon message on
Harsh, late or erratic automatic gearshifts
Transmission stuck in one gear or in a limp-home mode
Higher than normal shift pressure feel or firm engagement
Poor or inconsistent throttle response
Fuel economy worse than usual

Possible causes

Fault in the throttle position sensor or its circuit giving a high or incorrect signallikely
Damaged, chafed or shorted wiring in the throttle position PWM signal line, for example shorted to voltagelikely
Corroded, loose or pushed-out pins in the sensor or control module connectorslikely
Poor or missing ground or reference supply affecting the throttle position signalpossible
Throttle body fault or sticking throttle affecting the position readingpossible
Fault in the engine or transmission control module generating or interpreting the PWM signalrare
Outdated control module software where a known fault is documented for that modelrare

How to diagnose

Read all stored and pending codes and note freeze frame data, checking for other throttle, engine or transmission codes
Check for any technical service information that applies to the specific model, engine and transmission
Inspect the throttle position sensor, wiring and connectors for damage, corrosion, water ingress or chafing
Using live data, compare the reported throttle position with actual pedal and throttle movement from closed to wide open and check it moves smoothly
Check the sensor reference voltage, ground and signal at the connector against the manufacturer's specification, as the circuit layout depends on the model
Measure the PWM signal duty cycle with a suitable meter or scope and compare it with expected values across the throttle range
Check the signal wire for shorts to voltage and for continuity between the sensor and the control modules
Inspect the throttle body for sticking, carbon build-up or mechanical damage

How to fix

Repair or replace damaged wiring or the affected section of the signal circuit
Clean, repair or replace corroded or loose connectors and terminals
Replace the throttle position sensor, or the throttle body where the sensor is not sold separately
Restore faulty ground or reference supply connections
Clean or replace the throttle body if it is sticking or damaged
Update the control module software if a documented update exists, or repair or replace the module only after other causes are ruled out

Can I keep driving?

Medium severity

The car can usually be driven short distances, but erratic shifting or limp mode may make it unpredictable and can stress the transmission. Get it diagnosed soon and avoid heavy loads or hard driving until it is fixed.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.