P0124
UniversalThe Powertrain Control Module (PCM) detects an intermittent signal from the Throttle Position Sensor (TPS) or Accelerator Pedal Position Sensor (APP) 'A' circuit, indicating an inconsistent reading of throttle or pedal input.
Medium SeverityThis code signifies an inconsistent or intermittent signal from the throttle position sensor or accelerator pedal position sensor, which tells the engine computer how much throttle input the driver is requesting. An intermittent signal can lead to unpredictable engine behavior, including sudden loss of power, erratic idling, or unexpected acceleration.
⚠️ Before You Begin (Safety First)
Always wear appropriate personal protective equipment (PPE) when working on your vehicle. Ensure the vehicle is in Park or Neutral with the parking brake engaged. To avoid electrical shock or accidental engine starting, disconnect the negative battery terminal before performing any diagnostic or repair work involving electrical components. Exercise caution when working around hot engine components or moving parts.
Common Symptoms
- Erratic idle speed
- Engine hesitation during acceleration
- Sudden loss of engine power
- Engine stalling
- Cruise control malfunction
- Check Engine Light illuminated
- Unpredictable throttle response
Common Causes
- Loose, corroded, or damaged electrical connectors at the sensor or PCM
- Frayed, broken, or shorted wiring in the sensor circuit
- Intermittent fault within the Throttle Position Sensor (TPS) itself
- Intermittent fault within the Accelerator Pedal Position Sensor (APP) itself
- Damaged Powertrain Control Module (PCM) (rare)
Frequently reported on: Ford F-150 (2004-2008), Honda Accord (2003-2007), Chevrolet Silverado (2000-2006), Toyota Camry (2002-2006)
Diagnostic Steps
- Visually inspect the Throttle Position Sensor (TPS) or Accelerator Pedal Position Sensor (APP) and its wiring harness for any signs of damage, fraying, or corrosion.
- Check the electrical connectors at the sensor and the PCM for tightness and corrosion. Clean or repair as necessary.
- With a multimeter, test the sensor's output voltage while slowly moving the throttle plate or accelerator pedal. Look for any sudden drops, spikes, or intermittent readings.
- Wiggle the wiring harness while monitoring the sensor's output to identify any intermittent electrical breaks.
- If the sensor tests faulty or shows intermittent readings, replace the Throttle Position Sensor (TPS) or Accelerator Pedal Position Sensor (APP) as a unit. Ensure proper calibration if required after replacement.
- Clear the P0124 code from the PCM and test drive the vehicle to verify the repair.
👨🔧 When to Call a Professional
If you have replaced the sensor and thoroughly checked the associated wiring and connectors, but the intermittent issue persists, or if you suspect a deeper electrical system problem that requires advanced diagnostic tools, it is best to consult a qualified automotive technician. Intermittent issues can be complex to trace without specialized equipment.
Commonly Asked Questions
What does 'intermittent' mean in P0124?
Intermittent means the sensor signal is not consistently reliable; it might work sometimes and fail at other times, or provide erratic readings rather than a complete failure.
Can I drive with an intermittent P0124 code?
While it might be possible to drive, it's not recommended. The intermittent nature can lead to unpredictable engine behavior, including sudden power loss or acceleration, which is a significant safety hazard. Repair promptly.
Is the Throttle Position Sensor (TPS) the same as the Accelerator Pedal Position Sensor (APP)?
They serve similar functions but are located differently. The TPS is typically on the throttle body, measuring the throttle plate's position. The APP is on the accelerator pedal assembly, measuring pedal input. P0124 can refer to either 'Sensor/Switch A' depending on the vehicle's design.
How do I test for an intermittent electrical connection?
Use a multimeter to monitor the sensor's voltage output. While the meter is connected, gently wiggle and flex the wiring harness and connectors. A sudden change or drop in voltage on the multimeter indicates an intermittent connection issue in that area.
Will cleaning the sensor fix P0124?
Cleaning the sensor itself might not fix an internal intermittent fault. However, cleaning corroded electrical connectors with an electrical contact cleaner can often resolve issues caused by poor connections, which is a common cause for intermittent codes.