What P0105 means
The manifold absolute pressure (MAP) sensor measures the pressure behind the throttle; on vehicles without a separate barometric sensor it also supplies the ambient pressure, read at key-on or wide-open throttle – hence 'MAP/BARO'.
How the engine computer detects it
It is a three-wire sensor with 5 V reference, ground and signal. P0105 is the general circuit fault and is rarely used today: most gasoline engines report low, high and intermittent separately (P0107–P0109). It appears mainly where the fault cannot be broken down further – Ford's 2023 diesels set it when the digital SENT sensor reports a bad status or an out-of-limit value for 5 s (lost communication is a separate U code), and Bosch EDC16 diesels use it with a fault type byte, for example signal below 0.2 V. Saab then substitutes 101.3 kPa (15 psi), limits torque and switches off EGR and boost control.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Check engine light on
- Loss of power, limp mode with torque limit (diesel)
- Rough idle, hard starting, higher consumption (gasoline)
- Smoke possible on diesels
Common causes
- Connector or wiring to the sensor open, shorted or loose Most likely
- MAP sensor faulty (oiled, failed internally, SENT status fault) Possible
- Sensor hose disconnected, vacuum or boost leak Possible
- 5 V reference pulled down by another sensor on the same circuit Less likely
- Engine control module faulty Less likely
How to diagnose P0105
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: manifold absolute pressure sensor, sensor wiring, sensor reference voltage.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 1
- Fuel and air metering
- 05
- Specific fault
Questions drivers ask
Can I drive with code P0105?
Drive gently and only as far as you need to. The engine computer may limit power to protect the engine, so avoid highways and heavy traffic until it's fixed. If the check engine light starts flashing, pull over.
Will my car pass an emissions inspection with P0105?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
Will P0105 clear by itself?
The light can go off after several drive cycles without the fault, but the code returns if the cause is still there. After a repair, the readiness monitors need a full drive cycle before an inspection.
Can I fix P0105 myself?
Often yes, with an OBD-II scanner and basic tools. Difficulty: easy. Start with the cheapest checks before replacing expensive parts.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.