P1241 — Manifold absolute pressure (MAP) sensor 2 - signal too low at full load for low engine speed

Diagnostic algorithm

1. Retrieve code(s) and freeze-frame data. Note engine speed, throttle position, MAP voltage/pressure when fault set.
2. Visually inspect MAP sensor 2 and related wiring for physical damage, corrosion, or poor connections. Repair as needed.
3. With key ON (engine off) backprobe the MAP connector: verify stable 5 V reference, good ground, and signal voltage. Replace sensor if reference or ground missing.
4. Start engine and monitor live MAP signal while performing controlled tests: idle, partial throttle, and full-throttle at low RPM (with safety). Signal should increase with load. If signal remains low, suspect sensor/wiring.
5. Use a handheld vacuum/pressure pump (or safely apply pressure) to the MAP sensor while monitoring voltage. Confirm sensor responds across expected range. If it does not, replace the sensor.
6. If sensor bench-tests OK, perform continuity and resistance checks on signal, reference and ground wires back to the ECU; look for shorts to ground or +12 V and intermittent opens.
7. Inspect intake and boost system for leaks (spray soapy water if appropriate, or use smoke test), and verify turbo and boost control operation (wastegate actuator, boost control valve).
8. Repair wiring, connectors, intake leaks, or boost control faults as found. Clear codes and perform a road test under the same conditions to confirm the repair.
9. If wiring and components test good but the fault remains, consult manufacturer technical service info for ECU-related issues or software updates before replacing the ECU.