P1135

Code

Other P — Powertrain

Pedal Position Sensor A Circuit Intermittent

Brand: Other

Type: P — Powertrain

Views: UK: 38 EN: 67 RU: 37

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Page language: EN

Causes

Damaged or corroded pedal sensor connector
Broken, chafed, or shorted wiring in the pedal harness
Poor ground or reference voltage loss
Contaminated or water-damaged pedal sensor
Failed pedal position sensor (APPS)
Intermittent ECU/input module fault or connector problem

Symptoms

Malfunction Indicator Lamp (MIL) illuminated
Intermittent or delayed throttle response
Limp-home / reduced performance mode on some vehicles
Hesitation, surging, or uneven acceleration
Possible difficulty starting or stalling in rare cases

What to check

Retrieve freeze-frame and full DTC list with a scan tool; note conditions when fault set
Monitor live PID data for Pedal Position Sensor A (and B if present) while moving pedal slowly and quickly
Perform visual inspection of pedal sensor, connector, and wiring harness for damage, corrosion, or water intrusion
Wiggle test wiring and connectors while watching live data for dropouts or erratic values
Check for related codes (e.g., other pedal/throttle sensor or throttle actuator codes)
Inspect ECM connector and ground points if visible and accessible

Signal parameters

Reference voltage typically supplied by ECU: ≈5.0 V (vehicle-specific)
Signal voltage range across pedal travel: commonly ~0.5 V (closed) to ~4.5 V (wide open) — should change smoothly with pedal movement
Sensor ground near 0 V; no large fluctuation on ground line
No intermittent open/short spikes or sudden drops to 0 V when pedal is moved

Diagnostic algorithm

Connect a capable scan tool and record freeze-frame and live PIDs for Pedal Position Sensor A (and B if available). Note when intermittent occurs.
Perform a thorough visual inspection of the pedal sensor, connector, and harness — look for chafing at firewall, near footwell, or where harness flexes.
Backprobe the pedal sensor connector. With ignition on (engine off), confirm: reference voltage present (≈5 V), good sensor ground (≈0 V), and signal voltage changes smoothly with pedal travel.
While monitoring the signal PID or using a multimeter/oscilloscope on the signal wire, wiggle the harness and connector to reproduce the intermittent fault; check for sudden signal dropouts.
If there is a second pedal sensor (redundant channel B), compare A vs B signals for correlation or mismatch; an A/B disagreement supports sensor/harness fault.
Check continuity and resistance of signal, reference and ground wires between the pedal connector and the ECU connector. Repair any open or high-resistance circuits.
Inspect and clean connectors; repair or replace damaged terminals. Re-secure harness to prevent repeated flex fatigue.
If wiring and connectors are good but fault persists and signals are unstable, replace the pedal position sensor assembly.
After repairs, clear codes and road-test under the original conditions to verify the intermittent fault no longer occurs. If intermittent remains and wiring is verified, consider ECU/input module evaluation or replacement by qualified technician.

Likely causes

Frayed wiring where harness flexes at pedal or firewall
Pin corrosion or bent pins at pedal sensor connector
Loose terminal or partial break in signal wire causing open/short under vibration
Low or missing 5V reference from ECU due to connector fault
Internal sensor electronics failing intermittently

Fault status

⚠️ Status

P1135 - Pedal Position Sensor A Circuit Intermittent. Inspect pedal sensor, wiring, and connectors for intermittent open/short; verify signal and reference voltages.

🟡 Repair difficulty: Medium

⏱️ Diagnostic time: 1-3 hours