Code
P0069
MITSUBISHI
P — Powertrain
BARO./MAP sensor
Views:
UK: 17
EN: 18
RU: 66
AI status
Completed
Completed
100%
Causes
- Faulty BARO/MAP sensor
- Open, short or damaged wiring between sensor and ECM
- Corroded or loose connector
- Blocked, disconnected or leaking vacuum/pressure hose or sensor port
- Contaminated sensor (oil, debris)
- Incorrect reference voltage or poor ground
Symptoms
- Malfunction Indicator Lamp (MIL) / Check Engine Light illuminated
- Poor idle, engine hesitation or stumbling
- Stalling or rough running at idle or load
- Reduced power or limp-home mode in some vehicles
- Poor fuel economy and incorrect fuel trims
- Hard starting or extended cranking
What to check
- Read stored freeze frame and live data with a scan tool (MAP and BARO readings, fuel trims)
- Visually inspect sensor, connector and vacuum/pressure hoses for damage or disconnection
- Wiggle wiring harness and connector while monitoring live MAP signal for intermittent faults
- Check for intake vacuum leaks (smoke test or spray test where safe)
- Verify battery/charging voltage and ECM grounds
- Clear code and see if it returns after drive cycle
Signal parameters
- Sensor reference supply typically ~5.0 V (verify exact spec for vehicle)
- MAP signal voltage commonly in the range ~0.5–4.5 V (low vacuum → lower/higher depending on sensor design; confirm with manufacturer data)
- Barometric pressure at sea level ~101 kPa (sensor should report similar when key ON, engine OFF)
- Sensor ground continuity should be low (check for continuity to chassis/ECM ground)
- Live scan: MAP reading should change smoothly with throttle/vacuum; abrupt jumps or frozen value indicate fault
Diagnostic algorithm
- Retrieve DTC(s) and freeze frame data; note conditions when fault set (load, RPM, temp, boost).
- Visually inspect MAP/BARO sensor, connector and vacuum/sensor port for contamination, damage or loose/disconnected hoses.
- Backprobe sensor: verify reference (5V), ground, and signal voltage with key ON and engine running. Compare to expected ranges and live scan values.
- While monitoring MAP signal, change engine load (snap throttle, apply vacuum) and observe smooth correlated signal change. If signal doesn't respond, suspect sensor/wiring.
- Perform continuity/resistance checks on wiring between sensor and ECM; check for shorts to 12V or ground.
- Check for intake leaks (smoke test) and repair any leaks or blocked ports that could cause incorrect pressure readings.
- If wiring and vehicle-side circuits are good, substitute a known-good sensor or bench-test sensor per manufacturer's procedure.
- If replacement or repair performed, clear codes, re-run readiness/drive cycle and confirm code does not return.
- If fault persists after sensor replacement and wiring verified, evaluate ECM input circuits or consult repair manual for ECM testing.
Likely causes
- Failed MAP sensor (most common)
- Vacuum hose disconnected or intake leak near MAP port
- Wiring chafe/short where harness moves (heat/rubber wear)
- Corroded connector terminals or water ingress
- Sensor port clogged with oil/soot or foreign matter
- Recent service disturbed vacuum lines or connectors
Fault status
Status
BARO/MAP sensor circuit range/performance — sensor signal out of expected range or inconsistent with other inputs.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 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