U0124 – Lost Communication With Lateral Acceleration Sensor means the vehicle’s PCM, ABS module, or stability control module has stopped receiving data from the Lateral Acceleration Sensor (LAS). This sensor measures side-to-side G-forces and plays a key role in stability control, traction control, and rollover prevention. When communication is lost, the vehicle may disable these safety systems, trigger warning lights, or exhibit unstable handling. This guide explains what U0124 means, common symptoms, likely causes, diagnostic steps, and effective repair solutions.
What Does U0124 Mean?
U0124 is a generic network communication code indicating that the Lateral Acceleration Sensor is not responding over the CAN bus. This sensor is typically mounted near the vehicle’s centerline — often under the seat, in the console, or on the floor pan — where it measures lateral G-force. The LAS works together with the yaw rate and steering angle sensors to help the Vehicle Dynamics Control Module (VDCM) maintain stability.
If this sensor goes offline, the stability control module cannot accurately determine vehicle movement, so it may disable traction and stability features to avoid incorrect interventions. U0124 usually appears alongside other ESC or ABS-related codes.
Quick Reference
- OBD-II Family: U-Code (Network Communication)
- Scope: Generic
- System: Stability Control / Traction / CAN Bus
- Difficulty Level: Moderate
- Estimated Repair Cost: €120–€450+
- Last Updated: 21 November 2025
Real-World Example / Field Notes
A compact sedan arrived with the ESC and ABS lights illuminated after the owner reported sliding during a wet-road turn. The PCM, ABS, and VDCM all stored U0124. Inspection revealed that spilled liquid had seeped under the center console, causing corrosion on the LAS connector. Cleaning the connector restored communication and all lights cleared after a short drive.
In another case, an SUV intermittently disabled stability control while cornering. U0124 appeared intermittently. The root cause was a cracked CAN harness under the driver seat where a previous repair had stressed the wiring. Rebuilding the harness and securing it properly resolved the intermittent dropout conditions.
Symptoms of U0124 – Lost Communication With Lateral Acceleration Sensor
- ESC or VSC light activated: Stability control disabled.
- Traction control warning: Reduced traction on slippery roads.
- ABS warning light: ABS may be partially disabled.
- Unstable handling: Vehicle may slide or feel less controlled during turns.
- No response from lateral G-force sensor: Live data missing or frozen.
- Intermittent or complete loss of CAN communication: Scan tool cannot access the LAS.
- Related U-codes: Particularly U0122 and U0123.
Common Causes of U0124
Most Common Causes
- Loss of power or ground at the Lateral Acceleration Sensor
- Corroded or water-damaged connector under seats or console
- CAN bus wiring faults (shorts, opens, high resistance)
- Faulty Lateral Acceleration Sensor
- Damaged harness caused by seat movement or interior repairs
Less Common Causes
- Rodent damage under carpet or floor pan
- Poor chassis ground affecting stability control sensors
- Incorrect aftermarket wiring (audio amps, remote starters)
- Failed CAN terminating resistor
- Intermittent module overheating
Diagnosis: Step-by-Step Guide
U0124 diagnosis requires checking the sensor’s power supply, network integrity, and physical condition. Follow these steps carefully for accurate troubleshooting.
Tools You’ll Need
Advanced scan tool, multimeter, wiring diagrams, backprobe kit, CAN breakout box, oscilloscope (recommended), and battery/charging system tester.
- Scan all modules: Confirm U0124 in multiple modules and verify the LAS is not communicating.
- Locate the LAS: Usually under the center console, front seats, or floor pan.
- Check for water or liquid damage: Very common under seats and console areas.
- Verify power and ground: Use wiring diagrams to confirm correct voltage and grounding.
- Inspect connectors: Look for corrosion, bent terminals, moisture, or loose pins.
- Test CAN-H and CAN-L voltage: Expect ~3.5V (H) and ~1.5V (L). Incorrect readings indicate wiring issues.
- Measure 60-ohm network resistance: With ignition off, CAN-H to CAN-L should read ~60 ohms.
- Perform continuity testing: Trace wiring between the LAS and VDCM/ABS module.
- Use wiggle test: Move wiring under the seat/console and observe live data for dropouts.
- Oscilloscope waveform check: A failing sensor or wiring interference will produce distorted waveforms.
Pro Tip: Movement of front seats is a common cause of CAN and sensor wiring damage. Always inspect the harness around seat tracks and mounting brackets when diagnosing U0124.
Possible Fixes & Repair Costs
- Clean or repair LAS connector: €20–€80
- Repair or replace damaged CAN wiring: €60–€200
- Fix water intrusion or spilled-liquid damage: €50–€150
- Replace Lateral Acceleration Sensor: €150–€450+
- Replace damaged floor or seat harness sections: €120–€300
- Charging system repair (if voltage-related): €120–€400
Can I Still Drive With U0124?
Yes, but with reduced safety. With the LAS offline, the stability control system cannot accurately detect sideways movement, increasing the risk of skidding during turns or on wet roads. ABS and traction control may also function poorly. Avoid aggressive driving and repair the issue as soon as possible.
Related Codes
- U0151 – Instrument Panel Communication Fault
- U0141 – Steering System Network Communication Fault
- U0121 – Lost Communication With Anti-Lock Brake System (ABS) Control Module
- U0102 – Lost Communication With Transfer Case Control Module
- U0101 – Lost Communication With TCM
- U0100 – Lost Communication With ECM/PCM "A"
- U0195 – Lost Communication With Audio AMP
- U0194 – Lost Communication With Audio Display
- U0188 – Lost Communication With Video Display
- U0185 – Lost Communication With TV/Telematics Unit
Key Takeaways
- U0124 indicates the Lateral Acceleration Sensor has stopped communicating over the CAN bus.
- Corrosion, liquid spills, and seat movement are common causes.
- Stability and traction systems may be disabled, reducing vehicle safety.
- Diagnosis requires verifying power, grounding, and CAN network integrity.
FAQ
Where is the Lateral Acceleration Sensor located?
Often under the center console, under the front seats, or on the floor pan near the vehicle’s center of gravity.
Can spilled drinks cause U0124?
Yes. Spills in the console area commonly corrode the LAS connector or wiring.
Does U0124 mean the LAS is bad?
Not always. Most faults come from wiring or moisture damage rather than sensor failure.
Is it safe to drive with U0124?
Driving is possible but less safe. Stability and traction control may not function properly.
Should I replace the sensor immediately?
Only after verifying power, ground, connectors, and CAN integrity. Testing first saves unnecessary part replacements.