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P1573

Throttle Position Not Available.

  • Mercury
  • Powertrain
  • Manufacturer code
  • Medium severity

How this code is built

P
SystemPowertrain
1
Defined byThe manufacturer
5
AreaVehicle speed, idle control and auxiliary inputs
73
FaultThe specific fault in that area

What it means

P1573 on a Mercury means the powertrain control module cannot get a usable throttle position signal, so 'Throttle Position Not Available' is logged. The PCM saw the throttle position input missing, implausible or out of range, or the throttle position information it needs for torque or throttle control was not being supplied. The exact test and strategy vary with model, engine and year.

Symptoms

  • Engine warning light on
  • Reduced power or limp-home mode
  • Poor or unstable idle
  • Hesitation or flat spot when pulling away
  • Stalling or hard starting
  • Transmission shifting harshly or not as normal

Possible causes

  • Faulty throttle position sensor or throttle body assembly (worn track or internal fault)likely
  • Damaged wiring, chafing or poor connector contact in the throttle position sensor circuit (signal, reference or ground)likely
  • Dirty or sticking throttle body affecting throttle movement and the position signalpossible
  • Poor PCM power or ground supply causing erratic sensor readingspossible
  • Water or corrosion in the throttle body connector or harnesspossible
  • Internal PCM fault or outdated calibration, where a manufacturer update is known for the modelrare

How to diagnose

  1. Read all stored and pending codes and note the freeze frame data; look for other throttle, pedal or reference voltage codes that point to a shared fault.
  2. Check live data for throttle position while moving the throttle slowly from closed to fully open; look for dropouts, spikes or a reading that does not change.
  3. Visually inspect the throttle body connector and harness for corrosion, bent pins, chafing, heat damage or oil contamination.
  4. Check the throttle body for carbon build-up and free, smooth movement of the plate, following the procedure for the specific model.
  5. Check the sensor reference voltage, signal and ground at the connector against the manufacturer's specification for the engine fitted.
  6. Wiggle-test the harness with the engine idling and watch for changes in the signal or the fault resetting.
  7. Check the PCM power and ground supplies and the battery and charging voltage.
  8. Check for applicable service bulletins or calibration updates for the model before suspecting the PCM.

How to fix

  • Repair or replace damaged wiring, terminals or connectors in the throttle position circuit.
  • Replace the throttle position sensor or throttle body if the signal is faulty, then carry out any required relearn or adaptation.
  • Clean the throttle body carefully using the correct method for the model if contamination is found.
  • Repair poor PCM power or ground connections.
  • Apply a manufacturer calibration update or repair or replace the PCM only if testing confirms it is at fault.

Can I keep driving?

Medium severity

The car may run in a reduced-power mode and could stall or hesitate unpredictably, so avoid long journeys and busy roads and get it checked soon. If power loss or stalling occurs, stop driving until it is repaired.

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

This code for other makes

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