U0331 code meaning
Software Incompatibility With Body Control Module A
What U0331 means
Body control module A is the first of several body controllers on vehicles that spread lighting, locking, wipers and power distribution over more than one unit. With a single body controller the same mismatch is reported as U0322; U0339 covers unit B. U0331 means a partner module finds the software or configuration of unit A unfit. No manufacturer documents U0331 publicly, and none reveals which controller is labelled A. Jaguar calls its auxiliary junction box body control module B (recall J017), leaving the central junction box as the leading body unit; on 2016–2017 XF models that would not start with both smart keys inside, Jaguar reconfigured that box to the latest level (K424). Ford cured failed BCM installations on many 2016–2017 models with a newer IDS release (SSM 50097). Body functions may fail; no MIL.
U0331 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyWorkshop only
- Typical labor0.3 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0331
- Lighting, locking or wiper functions fail or behave oddly
- Keyless start or remote locking may not work
- Several modules store network codes after body module work
Common causes of U0331
- Most likelyBody control module A replaced without loading the vehicle configuration
- PossibleProgramming aborted or corrupted by an outdated diagnostic tool release
- Less likelyOther body modules updated while unit A stayed on its old level
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Body control module a
What each part of U0331 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 31 | The exact fault in that area. |
What to do next
- Note U0331 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 U0331
What does U0331 mean?
U0331 means "Software Incompatibility With Body Control Module A". Body control module A is the first of several body controllers on vehicles that spread lighting, locking, wipers and power distribution over more than one unit. It is a generic code, so it means the same on every make.
Is it safe to drive with U0331?
U0331 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0331 fail an emissions test?
U0331 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 U0331 to fix?
Difficulty: workshop only. A typical repair takes 0.3 to 2 hours of work. This is a job for a workshop.
Will U0331 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.