U0125 code meaning
Lost Communication With Multi-axis Acceleration Sensor Module A
What U0125 means
U0125 concerns the inertial measurement unit that bundles yaw rate plus lateral and longitudinal acceleration on one bus node. GM uses the code widely: the 2019 XT4 brake controller (EBCM) flags a missing IMU frame after 0.1 s, the 2025 object-detection module after 0.05 s and then disables adaptive cruise; both are Type C without MIL. Saab's 9-5 list adds symptom bytes 71, 72 and 74 for invalid data, wrong message counter and checksum. Field cases: a broken wire at connector X411 under the left rear (Equinox/Terrain, PIT5171B) and an EBCM reflash for 2020 Equinox (N192285670). Stellantis calls the part Dynamics Sensor. U0123/U0124 name single-axis modules instead.
U0125 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U0125
- Service ESC / StabiliTrak message, traction and ABS lamps
- Adaptive cruise control or all-wheel drive unavailable
- Electric parking brake warning on some models
Common causes of U0125
- Most likelyWire broken inside the insulation or rubbed through near a chassis connector (GM X411)
- PossibleLoose or corroded plug at the inertial sensor
- PossibleBrake controller software that drops the sensor (reflash released)
- Less likelyMulti-axis sensor internally faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Inertial sensor clusterCAN bus wiring
What each part of U0125 means
| U | Network system: communication between the control modules (CAN bus). |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 25 | The exact fault in that area. |
What to do next
- Note U0125 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 U0125
What does U0125 mean?
U0125 means "Lost Communication With Multi-axis Acceleration Sensor Module A". U0125 concerns the inertial measurement unit that bundles yaw rate plus lateral and longitudinal acceleration on one bus node. It is a generic code, so it means the same on every make.
Is it safe to drive with U0125?
U0125 does not normally turn on the check engine light by itself. Watch for the symptoms above and have it checked soon.
Will U0125 fail an emissions test?
U0125 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 U0125 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will U0125 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.