U0680 code meaning
Lost Communication With Barometric Pressure Sensor B
Network system Generic code U06xx codes Check engine light
What U0680 means
The letter B need not mean a second ambient sensor; it can be any further pressure input that sees near-atmospheric air. GM's 23OBDG07 and 24OBDG07 tables, written for a program with two throttle bodies, use barometric sensor B for the pressure ahead of the bank 2 throttle and send it over SENT. U0680 is stored when the frames carrying the high and low line pressure of bank 2 come in with a wrong data length code for 1.5 s; the MIL follows after two trips. The checks of the value itself are P222C and P222D (raw reading under 50 or over 115 kPa) and P222B (plausibility against ambient pressure). U068A covers the bank 1 counterpart. Air mass on bank 2 then has to be estimated without its reference.
U0680 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0680
- Check engine light after two trips
- Uneven running between banks possible
- Additional pressure plausibility codes
Common causes of U0680
- Most likelySENT signal, supply or ground wire to the bank 2 pressure sensor faulty
- PossibleConnector at the sensor ahead of the throttle loose or wet
- PossiblePressure sensor sends malformed frames
- Less likelyEngine controller software or SENT input fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Baro sensor bVehicle bus wiring
What each part of U0680 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 80 | The exact fault in that area. |
What to do next
- Note U0680 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U0680
What does U0680 mean?
U0680 means "Lost Communication With Barometric Pressure Sensor B". The letter B need not mean a second ambient sensor; it can be any further pressure input that sees near-atmospheric air. It is a generic code, so it means the same on every make.
Is it safe to drive with U0680?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will U0680 fail an emissions test?
Yes, it can. U0680 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is U0680 to fix?
Difficulty: medium. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U0680 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.