U0189 code meaning
Lost Communication With Digital Disc Player/Changer Module C
What U0189 means
U0189 covers the third disc player or changer on the bus, module C. Systems with more than one drive are found mostly in rear-seat entertainment or luxury setups, where a front unit and separate rear players feed different screens. The head unit or another listener stores U0189 once module C's cyclic messages stop arriving; GM describes this mechanism for all U0100-U02FF codes, with voltage required to be between 9 and 16 V. No manufacturer documents U0189 publicly, and GM's published list contains no disc player codes. U0187 and U0188 name modules A and B, U0190 module D. Check whether the vehicle really has a third drive before chasing wiring. Only that source fails; no MIL, no effect on driving.
U0189 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0189
- Rear or third disc source unavailable
- Rear screen shows no disc content
- Code stored in the head unit
Common causes of U0189
- Most likelyDisc unit C fuse blown or ground loose
- PossibleConnector or bus wiring to the rear player damaged
- PossibleVehicle coded for a third drive that is not fitted
- Less likelyDisc player/changer C faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Disc player moduleCAN bus wiring
What each part of U0189 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 U0189 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 U0189
What does U0189 mean?
U0189 means "Lost Communication With Digital Disc Player/Changer Module C". U0189 covers the third disc player or changer on the bus, module C. It is a generic code, so it means the same on every make.
Is it safe to drive with U0189?
U0189 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0189 fail an emissions test?
U0189 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 U0189 to fix?
Difficulty: easy. A typical repair takes 0.3 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will U0189 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.