U0076 code meaning
Control Module Communication Bus D Off
Network system Generic code U00xx codes Check engine light
What U0076 means
GM is the main public user of U0076. In the 2019 tables for the Corvette LT5 engine, Bus D is the Powertrain Sensor CAN, a private link between the ECM and engine-side devices. The ECM sets the code when that bus has been off for one second after the controller has run for three seconds, Type B with MIL after two trips, and holds back its lost-message check toward the fuel level module meanwhile. On the 2020-22 Malibu 1.5 L, bulletin 21-NA-186 traces U0076 together with U18A2 and message counter faults to an ECM harness rubbing on its bracket; owners notice a Service Engine Soon lamp or an erratic fuel gauge. Unlike U0055, which describes the bus D wiring as a whole, this code reports that the ECM's own controller has fallen silent.
U0076 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0076
- Service Engine Soon lamp or MIL on
- Fuel gauge erratic or wrong
- Message counter codes stored alongside
Common causes of U0076
- Most likelyECM harness rubbing through on its bracket
- PossiblePoor contact at a connector of the engine-side sensor bus
- Less likelyFaulty CAN transceiver inside the ECM
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Bus d wiringCAN transceiver
What each part of U0076 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 76 | The exact fault in that area. |
What to do next
- Note U0076 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 U0076
What does U0076 mean?
U0076 means "Control Module Communication Bus D Off". GM is the main public user of U0076. It is a generic code, so it means the same on every make.
Is it safe to drive with U0076?
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 U0076 fail an emissions test?
Yes, it can. U0076 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 U0076 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U0076 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.