U047D code meaning
Invalid Data Received From Restraints System Sensor M
What U047D means
U047D reports invalid data from restraints sensor M; U017C is lost contact. A thirteenth satellite exceeds the twelve sensor interfaces of Bosch's standard airbag control unit, so a system using M needs a larger controller such as Bosch's AB premium with up to 18. No manufacturer discloses which component is M. The fault lies in content, not in the link: a wrong sensor variant, a damaged sensor or controller software that misreads the data are typical suspects. Airbag lamp on, no MIL.
U047D at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyHard
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U047D
- Airbag warning lamp on
- Code stored in the restraints controller
Common causes of U047D
- PossibleSensor variant not matching the vehicle configuration
- PossibleDamaged satellite sensor
- Less likelyRestraints controller software misinterpreting the sensor data
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Restraints system sensor m
What each part of U047D means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 7D | The exact fault in that area. |
What to do next
- Note U047D 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 U047D
What does U047D mean?
U047D means "Invalid Data Received From Restraints System Sensor M". U047D reports invalid data from restraints sensor M; U017C is lost contact. It is a generic code, so it means the same on every make.
Is it safe to drive with U047D?
U047D does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U047D fail an emissions test?
U047D 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 U047D to fix?
Difficulty: hard. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U047D clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.