U044A code meaning
Invalid Data Received From Serial Data Gateway Module D
What U044A means
U044A covers serial data gateway module D. A receiver records it when D's frames carry implausible values or violate their counter or checksum; if they stop, U0149 is the matching code. No manufacturer explains U044A publicly, but Stellantis shows which unit can hold the letter D: for the 2021 Jeep Grand Cherokee, case S2108000139 describes the driver assistance module logging U0149-00, which Stellantis words as lost contact to the security gateway, together with a brief Traffic Sign Assist message at start-up; no repair is needed and a camera module software update was announced. On such vehicles invalid data from the security gateway would therefore mainly affect assistance and display functions. As with the other gateway codes, software levels and supply are checked before hardware is replaced.
U044A 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 U044A
- Brief assistance unavailable message at start-up
- Driver assistance or display functions limited
Common causes of U044A
- PossibleReceiver software (e.g. camera or assistance module) misjudges gateway data at start-up
- PossibleSoftware or configuration of gateway D not matching the vehicle
- Less likelySupply, ground or bus wiring fault at gateway D
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Gateway module dCAN bus wiring
What each part of U044A means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 4A | The exact fault in that area. |
What to do next
- Note U044A 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 U044A
What does U044A mean?
U044A means "Invalid Data Received From Serial Data Gateway Module D". U044A covers serial data gateway module D. It is a generic code, so it means the same on every make.
Is it safe to drive with U044A?
U044A does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U044A fail an emissions test?
U044A 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 U044A to fix?
Difficulty: workshop only. A typical repair takes 0.3 to 2 hours of work. This is a job for a workshop.
Will U044A clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.