Audi P1543: Throttle Actuation Potentiometer Signal Too Low

What Does The Audi P1543 Code Mean?

Engine started, battery voltage must be at least 11.5v, all electrical components must be off, parking brake must be engaged (to keep daytime driving lights off), automatic transmission selector must be in park, the exhaust system must be properly sealed between the catalytic converter and the cylinder head, coolant temperature must be at least 80 degrees Celsius, and the ground between the engine and the chassis must be well connected. The signal from the Throttle Position Valve Module to the ECM detected was erratic, non existent or unreliable.

Note:

• If the complete throttle valve control module is current-less (e. g. connector disconnected) the throttle valve moves into a particular, specified mechanical position, which signals an increased idle speed with an engine at operating temperature. If only the Throttle Position (TP) actuator –V60- is current-less, the throttle valve also moves into the specified mechanical position (emergency running gap), however, since Closed Throttle Position (CTP) switch –F60- can still be recognized, an “almost normal idle RPM” is reached via the respective ignition angle retardation.
• If the Engine Control Module (ECM) detects a malfunction at Throttle Position (TP) sensor –G69-, Throttle Position (TP) actuator –V60- is switched current-less by the Engine Control Module (ECM) and the throttle valve moves into the specified mechanical position (emergency running gap) again.
• Terminal assignment at throttle control module is different in vehicles with and without cruise control.
• Characteristic: Steering column switch with operating module for cruise control.

What Are The Potential Causes Of The Audi P1543 Code?

Below are some potential causes of this DTC:

• Throttle valve control module is faulty
• Throttle valve is damaged or dirty
• Throttle valve must be in closed throttle position
• Accelerator pedal is out of adjustment (AEG engines only)
• Throttle position actuator is shorting to ground or power

Recommended Parts

Below are some recommended auto parts to help you address the trouble code affecting your vehicle and get it running smoothly again:

>>> IRONTREE S20070 Professional Electronic Throttle Body Compatible with 05-19 Audi
>>> 2Pcs Throttle Position Sensor & Idle Air Control Valve
>>> Hellla 010946011 Accelerator Pedal Sensor
>>> Audi Throttle position sensor

Note: During the purchasing process, please check carefully whether the part you want to buy fits your car!

Reference Sources

Audi A4 Avant 95-01 Service Repair Manual, page 54.