Code
P0235
GWM
P — Powertrain
- Malfunction in the turbocharger sensor circuit A
AI status
Completed
Completed
100%
Causes
- Damaged or failed boost/charger pressure sensor (sensor A)
- Open, shorted or chafed signal/ground/power wiring between sensor and ECU
- Corroded or loose sensor connector or pins
- Blocked, disconnected or leaking boost/vacuum reference hose or fitting
- Poor ECU power or ground at the circuit
- Internal ECU fault (rare)
Symptoms
- Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
- Reduced engine power or limp mode
- Poor acceleration, turbo lag or inconsistent boost
- Black smoke or increased fuel consumption (diesel/gas turbocharged engines)
- Rough idle or hesitation under load
What to check
- Read and record DTC(s) and freeze frame data with a scan tool
- View live data for turbo/boost sensor A signal while key on and during rev/road test
- Visually inspect sensor, wiring harness, connector and boost/vacuum hoses for damage/corrosion
- Backprobe sensor connector to check reference voltage, signal voltage and ground
- Check continuity and resistance of signal/ground wires to the ECU
- Wiggle wiring and connector while observing live data for intermittent faults
Signal parameters
- Sensor is typically supplied by a 5 V reference (verify with scan tool/multimeter)
- Normal signal output usually within 0.5–4.5 V proportional to boost pressure (varies by vehicle/sensor)
- Near 0 V suggests open circuit or short to ground; near battery voltage suggests short to Vb
- Signal should change smoothly with engine load/boost; jumping, flatline, or erratic values indicate a fault
Diagnostic algorithm
- Verify the P0235 code and any related codes. Record freeze frame and live data.
- Inspect sensor, connector and vacuum/boost hose for physical damage or contamination. Repair as needed.
- With connector connected, backprobe and check: a) 5 V reference (key ON), b) sensor ground, c) sensor signal at key ON and while cranking / running. Compare to expected ranges.
- If reference or ground missing, trace and repair wiring to power/ground source or ECU; check fuses and connectors.
- Check continuity between sensor signal and ECU pin; repair shorts/opens. Perform wiggle test for intermittent faults.
- If wiring and power/ground are OK but signal out of range, remove and bench-test or substitute a known-good sensor.
- Inspect/replace any blocked or leaking boost/vacuum hoses that affect sensor reading.
- If fault persists after sensor and wiring verified, check ECU inputs and grounds; consult manufacturer wiring diagrams and perform ECU tests.
- Clear codes and perform road test to confirm repair; monitor live boost/sensor data for stability.
Likely causes
- Failed boost pressure sensor
- Wiring harness damage at engine/heat areas or near turbo
- Corroded/loose connector at sensor
- Vacuum/boost hose leak or restriction affecting sensor reading
Fault status
Status
Malfunction detected in turbocharger/boost pressure sensor circuit A. MIL illuminated and DTC stored — signal open/short or out of range.
Repair difficulty: Medium
Diagnostic time: 0.5-2.5 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