U0289 code meaning
Lost Communication With DC/AC Converter Control Module B
What U0289 means
U0289 belongs to a second DC/AC converter, unit B, in vehicles that generate mains-voltage alternating current at two points, for example a small inverter for a console socket and a stronger one for the bed, or one converter per group of outlets. No manufacturer documents U0289 or describes a converter B in public material. Unit A shows how such a check behaves: GM's body control module on the 2026 Colorado and Canyon flags lost contact as U0288, falsely even on trucks without the outlet. GM's 2023 Silverado and Sierra programme, which later activated the inverter for dashboard and bed outlets by adding a power control module and reprogramming the BCM, shows that option coding decides which converters the network expects. Only the sockets fed by B should fail.
U0289 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.3 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0289
- Some outlets dead while others still work
- Power outlet warning message
Common causes of U0289
- PossibleNetwork configured for a second converter that is missing or not activated
- PossibleNo supply or ground at converter B (fuse, connector)
- PossibleBus wiring or connector to converter B damaged
- Less likelyConverter B internally failed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Dc ac converter module bVehicle bus wiring
What each part of U0289 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 89 | The exact fault in that area. |
What to do next
- Note U0289 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 U0289
What does U0289 mean?
U0289 means "Lost Communication With DC/AC Converter Control Module B". U0289 belongs to a second DC/AC converter, unit B, in vehicles that generate mains-voltage alternating current at two points, for example a small inverter for a console socket and a stronger one for the bed, or one converter per group of outlets. It is a generic code, so it means the same on every make.
Is it safe to drive with U0289?
U0289 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0289 fail an emissions test?
U0289 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U0289 to fix?
Difficulty: medium. A typical repair takes 0.3 to 3 hours of work. This is a job for a workshop.
Will U0289 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.