U067F: Lost Communication With Barometric Pressure Sensor A

What it means

The vehicle bus reports loss of communication with smart barometric pressure sensor A. Altitude correction for engine fueling and EVAP diagnostics switches to a substitute value.

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

Barometric pressure sensor A is a networked sensor that reports atmospheric pressure, which the engine controller can use for altitude-related fueling and evaporative-emissions checks. This code sets when the vehicle network stops receiving messages from sensor A, so those calculations may use a substitute pressure value.

Common causes

Most likely first.

1. Bus wiring open or shorted
2. Module without power or ground
3. 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

1. Save the freeze-frame data and scan all modules for communication codes to see whether sensor A disappeared alone or as part of a wider network fault.
2. Check live data for barometric pressure and sensor A's communication status, and compare them with other pressure readings if available.
3. Inspect sensor A's connector and nearby bus wiring for loose pins, corrosion, water, chafing, or damage.
4. Check the sensor's power and ground under the conditions specified by the manufacturer, since a supply fault can make a healthy sensor go offline.
5. Test the bus wiring for opens or shorts using the manufacturer's procedure, then assess sensor A or its control module only after wiring and power checks pass.

Common fixes

• Reconnect or clean a loose or corroded sensor A connector.
• Repair damaged bus wiring or terminals in sensor A's network branch.
• Restore a missing power or ground connection to the sensor or its module.
• Replace sensor A or its module if network, power, and ground tests isolate an internal failure.

Can I keep driving?

If the engine runs normally and no other systems are affected, a short, gentle trip may be possible, but arrange diagnosis soon because altitude compensation and some EVAP checks may be degraded. Stop if the vehicle develops drivability problems or other warnings.