What it means
The vehicle bus reports loss of communication with smart MAP sensor B. Engine load calculation switches to a fallback model based on MAF and RPM.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
How it works
A smart MAP sensor B reports manifold pressure data to the engine control module over the vehicle network. U060A sets when the module stops receiving sensor B's messages and must estimate engine load using its fallback model, including MAF and engine speed data.
Common causes
Most likely first.
- Bus wiring open or shorted
- Module without power or ground
- Module failed
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Record freeze-frame data and scan all modules for communication codes to identify when MAP sensor B data disappeared and whether other network faults are present.
- Compare live MAP sensor A and B readings, where available, and check whether only sensor B is missing or fixed.
- Inspect sensor B's connector and bus wiring for loose terminals, corrosion, chafing, or shorts.
- Check sensor B's power and ground circuits against the manufacturer's specification.
- Test the network wiring serving sensor B for opens or shorts, then assess the sensor module if wiring and supplies pass.
Common fixes
- Reconnect or clean sensor B's connector.
- Repair damaged or shorted bus wiring to MAP sensor B.
- Restore sensor B's power or ground connection.
- Replace MAP sensor B's module if its network path and supplies are sound but it remains offline.
Can I keep driving?
A short, gentle trip may be possible if the engine runs smoothly, but fallback load estimates can affect fueling and emissions. Avoid heavy acceleration if power or drivability is reduced, and repair the fault promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.