OBD-II trouble code
U0123: Lost Communication with Yaw Rate Sensor Module
A module on the network can no longer hear from the yaw rate sensor module, which tells the stability system how fast the vehicle is rotating. Usually a power, ground, or wiring fault, it typically disables stability control and lights the ESC and ABS warnings.
Quick facts
- System
- Network
- Category
- Network Communication
- Severity
- High severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $130 – $900
- DIY difficulty
- Advanced DIY
What does U0123 mean?
U0123 is set when a module on the vehicle's communication network — usually the stability or ABS controller — stops receiving messages from the yaw rate sensor module. The yaw rate sensor measures how quickly the vehicle is rotating around its vertical axis, which is exactly the information electronic stability control needs to detect the start of a skid or spin. Many vehicles combine the yaw rate and lateral acceleration sensors into one module. When the network loses contact with it, U0123 records that the sensor module has gone silent.
The causes are the usual lost-communication faults. The module may have lost power or ground through a blown fuse, corroded ground, or failed relay. The communication wiring or a connector at the module can be damaged, chafed, or corroded. The module's internal communication circuitry can fail, or another module on the bus can disrupt the network for everyone. Low 12-volt system voltage is a common cause of intermittent dropouts.
Without yaw rate data, the stability system can't tell whether the vehicle is rotating as the driver intends, so it shuts down stability and traction control as a fail-safe and lights the ESC and ABS warnings, often with the check engine light. Base brakes and steering still work, so the car is driveable, but the electronic protection against skids and spins is offline. Because stability control is a safety system, U0123 should be diagnosed promptly.
Common causes
- Blown power or ground fuse for the yaw rate sensor module
- Corroded or loose ground at the sensor module
- Damaged or chafed communication wiring to the module
- Corroded or backed-out terminals at the module connector
- Failed internal communication circuitry in the sensor module
- Another module on the bus disrupting network communication
- Low 12-volt system voltage from a weak or failing battery
- Sensor module knocked loose or damaged (it is often floor-mounted)
Symptoms
- Stability control (ESC) and traction control warning lights on
- ABS warning light on
- Check engine light may also be on
- Stability and traction control disabled
- Scan tool can't communicate with the yaw rate sensor module
- Base brakes and steering still function normally
- Symptoms may be intermittent with a marginal connection
Diagnostic steps
- 1.Scan all modules; confirm the yaw rate sensor module is unreachable while others respond.
- 2.Check the module's power and ground fuses, relays, and ground points.
- 3.Inspect the communication wiring and connector at the module for chafing, corrosion, and loose terminals.
- 4.Verify the sensor module is securely mounted and undamaged, since it is often located low in the vehicle.
- 5.Measure the communication bus lines at the module connector and verify continuity back to the bus.
- 6.Test the 12-volt battery and charging, since low voltage can cause intermittent communication loss.
- 7.If power, ground, and wiring are good but the module still won't communicate, suspect an internal sensor-module fault requiring replacement and possibly calibration.
Repair cost
$130 – $900
A blown fuse, corroded ground, or connector repair is the cheapest fix at $130-$350 once located. Wiring repair runs $200-$600. Diagnostic time often adds $100-$200. Replacing a yaw rate / combined dynamics sensor module typically runs $300-$900 including any required calibration, and is a last resort after wiring, power, and ground are ruled out.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with module communication / can bus diagnosis preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an advanced DIY job. It typically requires specialty tools, scan-tool access, lifting equipment, or careful sequencing to avoid causing new failures. Plan for extended downtime and have a backup vehicle. Most owners are better served by a shop that has done this repair before.