U0122

Lost Communication With Vehicle Dynamics Control Module

Communication network (stability control) Generic OBD-II Medium

What it means

U0122 means the network has lost communication with the vehicle dynamics (stability control) module, which manages ESP/ESC and traction control. With the module offline those systems shut down and their warning lights come on. The car still drives, steers, and brakes, but you lose the electronic help that keeps it stable in hard cornering or on slippery roads, so it's worth fixing promptly.

Medium

Can I keep driving? The car drives and brakes normally, but stability and traction control are disabled — drive gently, especially in the wet or snow, until it's fixed.

Real-world scan data

Seen in

431

scans in the past year

Found in

0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of U0122 scans

U0100in 29.5% of scans

U0121in 26.2% of scans

U0155in 25.8% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Stability control (ESP/ESC), traction, and often ABS warning lights on
Stability and traction control disabled
Vehicle dynamics/stability module missing when scanned
Related chassis U-codes stored alongside it

Common causes

Most likely first

Open, shorted, or chafed CAN wiring to the vehicle dynamics moduleLikely
Corroded or loose connector at the moduleCommon
Blown fuse or lost power/ground to the moduleCommon
Failed vehicle dynamics control moduleLess often
Bus fault preventing the module from reportingLess often

How to diagnose & fix

Work through it in order

Scan all modules and confirm the vehicle dynamics module is offline.
Check its power, ground, and fuse feeds.
Inspect wiring and the connector at the module for damage or corrosion.
Test the CAN bus lines to the module for open or short.
If wiring and power check out, replace the module, clear the code, and confirm stability control returns.

FAQ

Quick answers

Is it safe to drive with U0122?+

The brakes and steering still work, but stability and traction control are off, so the car is more likely to slip in hard cornering or on slick roads. Drive cautiously and get it fixed soon.

Can I just clear U0122?+

It comes back while the module stays offline. The underlying wiring, power, or module fault has to be repaired.

Read & clear U0122 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX