What does it mean?
P1743 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: Throttle Position Signal Invalid Data Received .
Symptoms
- MIL (check engine lamp) on and often a throttle related code stored as well
- Shift points wander, arriving too early or far too late for the pedal position
- No kickdown when the pedal is pressed hard
- Harsh or slipping shifts because line pressure is calculated from bad data
- Limp mode, hesitation and generally poor drivability
Likely causes
- Worn throttle position sensor with dead spots or a drifting output
- Faulty accelerator pedal position sensor sending implausible values
- Open, shorted or high resistance in the shared throttle signal wiring
- Corroded splice or connector on the reference, signal or ground circuit
- Poor module grounds shifting the signal reference between modules
- Communication bus fault so the throttle value never arrives or arrives corrupted
- Engine control side fault or outdated software broadcasting bad data
How to fix it
- Read codes on every module first, since a throttle sensor code usually explains this one
- Watch throttle percentage on live data through a slow full sweep and look for dropouts or flat spots
- Measure reference voltage, signal voltage and ground at the sensor with a multimeter
- Perform voltage drop tests on the shared ground and check common splices for corrosion
- Check the communication bus for errors and confirm both modules see the same value
- Repair the wiring, clean the connectors and correct any grounding fault found
- Replace the throttle or pedal sensor after verification, and address engine side faults or software last