Code
P2124
Generic
P — Powertrain
Throttle/Pedal Position Sensor/Switch D Circuit Intermittent
Views:
UK: 16
EN: 22
RU: 17
AI status
Completed
Completed
100%
Causes
- Poor or intermittent electrical connection at pedal or throttle body connector
- Damaged, frayed, or chaffed wiring harness (intermittent open/short/ground)
- Corroded or contaminated connector pins
- Failed pedal position sensor or throttle position sensor (channel D)
- Water intrusion or compression at connector
- Intermittent PCM input or internal PCM fault (less common)
Symptoms
- Intermittent Check Engine Light (CEL) or MIL illumination
- Transient or intermittent loss of throttle response
- Unexpected limp/home mode activation under some conditions
- Hesitation, surging, or inconsistent idle or acceleration
- Often no symptoms between occurrences (intermittent nature)
What to check
- Read freeze frame and live data with a scan tool; capture conditions when code set
- Visually inspect connectors and wiring for damage, corrosion, or water
- Back-probe the sensor D signal, reference (5V) and ground with a multimeter/oscilloscope
- Wiggle wiring harness and connectors while monitoring live signal for intermittent changes
- Perform resistance/continuity checks from sensor connector to PCM pin (engine off)
- Compare measured voltages to known-good channels (other pedal/throttle channels) if present
Signal parameters
- Reference voltage: nominally +5 V supply (varies by manufacturer) — should be stable
- Signal voltage: typically ~0.5 V (closed) to ~4.5 V (wide open) for an analog potentiometer-style sensor
- Sensor output should change smoothly with pedal/throttle movement without sudden jumps or dropouts
- Open-circuit: voltage may rise to reference or float unpredictably; short to ground: ~0 V; short to battery: ~5 V (or system voltage)
- Impedance: generally a few kΩ for potentiometer sensors (consult vehicle-specific data)
- Frequency: usually not a pulsed signal (unless digital sensor); monitor for noise or intermittent spikes with oscilloscope
Diagnostic algorithm
- Connect a capable scan tool and note freeze frame / live data when the code set. Capture pedal/throttle channel D while performing slow pedal movements.
- Visual inspection: inspect the pedal/throttle sensor connectors, harness routing, and PCM connector for corrosion, bent pins, damage, or water entry.
- Backprobe: with ignition ON (engine off), measure reference voltage, sensor D signal voltage and ground at the sensor connector. Verify reference is stable and ground has low resistance to chassis/PCM ground.
- Wiggle test: with live data displayed, gently wiggle the harness and connectors from the sensor to the PCM and along splice points. Look for momentary signal dropouts or erratic values that reproduce the fault.
- Continuity/resistance: with battery disconnected, check continuity/resistance between sensor signal pin and PCM input pin. Check for intermittent opens by flexing harness while measuring.
- Swap/compare: if vehicle has multiple channels/sensors, compare channel behavior or swap with a known-good sensor (where practical) to isolate sensor vs wiring/PCM.
- Repair: repair or replace any damaged wiring, clean or replace corroded connectors, secure and protect the harness (heat shrink, conduit). Replace sensor if testing indicates internal intermittent failure.
- Verify: clear codes, perform drive cycle and reproduce conditions to confirm code does not return. If intermittent remains and wiring and sensor test good, consult manufacturer diagnostic for PCM intermittent input checks or perform PCM bench/scan-tool tests.
- Safety note: secure the vehicle and avoid moving parts when performing live back-probing or wiggle tests; follow vehicle manufacturer safety procedures.
Likely causes
- Loose connector clip or partially backed-out terminal at sensor
- Broken wire inside harness that shifts when engine or pedal is moved
- Corrosion at the sensor connector causing intermittent contact
- Sensor internal intermittent (temperature or vibration dependent)
- Poor ground at a common ground point feeding the sensor circuit
Fault status
Status
Intermittent fault recorded on throttle/pedal position sensor/switch D circuit. PCM detected unstable or inconsistent signal input; fault may not be present continuously. Diagnostic data (freeze frame/live) should be used to capture event conditions before repair.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
P2124
MITSUBISHI
P — Powertrain
APS(main) intermittent
Views:
UK: 7
EN: 14
RU: 7
AI status
Completed
Completed
100%
Causes
- Poor or intermittent electrical connection at pedal or throttle body connector
- Damaged, frayed, or chaffed wiring harness (intermittent open/short/ground)
- Corroded or contaminated connector pins
- Failed pedal position sensor or throttle position sensor (channel D)
- Water intrusion or compression at connector
- Intermittent PCM input or internal PCM fault (less common)
Symptoms
- Intermittent Check Engine Light (CEL) or MIL illumination
- Transient or intermittent loss of throttle response
- Unexpected limp/home mode activation under some conditions
- Hesitation, surging, or inconsistent idle or acceleration
- Often no symptoms between occurrences (intermittent nature)
What to check
- Read freeze frame and live data with a scan tool; capture conditions when code set
- Visually inspect connectors and wiring for damage, corrosion, or water
- Back-probe the sensor D signal, reference (5V) and ground with a multimeter/oscilloscope
- Wiggle wiring harness and connectors while monitoring live signal for intermittent changes
- Perform resistance/continuity checks from sensor connector to PCM pin (engine off)
- Compare measured voltages to known-good channels (other pedal/throttle channels) if present
Signal parameters
- Reference voltage: nominally +5 V supply (varies by manufacturer) — should be stable
- Signal voltage: typically ~0.5 V (closed) to ~4.5 V (wide open) for an analog potentiometer-style sensor
- Sensor output should change smoothly with pedal/throttle movement without sudden jumps or dropouts
- Open-circuit: voltage may rise to reference or float unpredictably; short to ground: ~0 V; short to battery: ~5 V (or system voltage)
- Impedance: generally a few kΩ for potentiometer sensors (consult vehicle-specific data)
- Frequency: usually not a pulsed signal (unless digital sensor); monitor for noise or intermittent spikes with oscilloscope
Diagnostic algorithm
- Connect a capable scan tool and note freeze frame / live data when the code set. Capture pedal/throttle channel D while performing slow pedal movements.
- Visual inspection: inspect the pedal/throttle sensor connectors, harness routing, and PCM connector for corrosion, bent pins, damage, or water entry.
- Backprobe: with ignition ON (engine off), measure reference voltage, sensor D signal voltage and ground at the sensor connector. Verify reference is stable and ground has low resistance to chassis/PCM ground.
- Wiggle test: with live data displayed, gently wiggle the harness and connectors from the sensor to the PCM and along splice points. Look for momentary signal dropouts or erratic values that reproduce the fault.
- Continuity/resistance: with battery disconnected, check continuity/resistance between sensor signal pin and PCM input pin. Check for intermittent opens by flexing harness while measuring.
- Swap/compare: if vehicle has multiple channels/sensors, compare channel behavior or swap with a known-good sensor (where practical) to isolate sensor vs wiring/PCM.
- Repair: repair or replace any damaged wiring, clean or replace corroded connectors, secure and protect the harness (heat shrink, conduit). Replace sensor if testing indicates internal intermittent failure.
- Verify: clear codes, perform drive cycle and reproduce conditions to confirm code does not return. If intermittent remains and wiring and sensor test good, consult manufacturer diagnostic for PCM intermittent input checks or perform PCM bench/scan-tool tests.
- Safety note: secure the vehicle and avoid moving parts when performing live back-probing or wiggle tests; follow vehicle manufacturer safety procedures.
Likely causes
- Loose connector clip or partially backed-out terminal at sensor
- Broken wire inside harness that shifts when engine or pedal is moved
- Corrosion at the sensor connector causing intermittent contact
- Sensor internal intermittent (temperature or vibration dependent)
- Poor ground at a common ground point feeding the sensor circuit
Fault status
Status
Intermittent fault recorded on throttle/pedal position sensor/switch D circuit. PCM detected unstable or inconsistent signal input; fault may not be present continuously. Diagnostic data (freeze frame/live) should be used to capture event conditions before repair.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email