U044B code meaning
Invalid Data Received From Battery Energy Control Module C
What U044B means
A third battery controller, module C, appears where a pack is divided into separately managed sections or a vehicle has more than one battery system. A receiver, typically the hybrid or vehicle controller, sets U044B when C's frames on cell voltages, temperatures, state of charge or contactor status fail validity checks; U014A is lost contact, U0412 and U0413 cover modules A and B. No manufacturer documents U044B publicly. Volkswagen group documents number such controllers: Bentley bulletin 2051553/2 for the 2017-18 Bentayga logs battery and sensor faults under battery management 2, the unit serving the dynamic ride roll control. Expect reduced electric power or a hybrid system warning, since the receiver cannot rely on the pack data.
U044B at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor0.5 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U044B
- Hybrid or battery system warning
- Reduced electric power or range
- Functions supplied by the affected battery switched off
Common causes of U044B
- PossibleSoftware of battery module C not matching the vehicle controller
- PossibleFaulty cell or temperature sensing inside the pack section managed by C
- Less likelyBus wiring, connector or 12 V supply fault at module C
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Battery energy module cCAN bus wiring
What each part of U044B means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4B | The exact fault in that area. |
What to do next
- Note U044B 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 U044B
What does U044B mean?
U044B means "Invalid Data Received From Battery Energy Control Module C". A third battery controller, module C, appears where a pack is divided into separately managed sections or a vehicle has more than one battery system. It is a generic code, so it means the same on every make.
Is it safe to drive with U044B?
Drive gently and only to a workshop. With U044B the car can go into limp mode (reduced power) to protect itself.
Will U044B fail an emissions test?
U044B 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 U044B to fix?
Difficulty: workshop only. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will U044B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.