What Are the EBS Fault Codes for Trucks? Full List & Troubleshooting Guide

A complete technical guide explaining EBS fault codes used in trucks and semi trailers — including WABCO, Knorr-Bremse and Haldex systems, error groups, diagnostics and common repair steps.

📅 Published on 2025-12-01 | ✍️ Semi Trailer News Technical Desk

Image: Electronic Braking System (EBS) diagnostics on modern heavy trucks

🔧 What Are EBS Fault Codes?

EBS (Electronic Braking System) fault codes are numerical or alphanumeric messages stored by the ECU of WABCO, Knorr-Bremse, Haldex and OEM truck systems. These codes help diagnose:

wheel speed sensor failures
EBS modulator valve problems
CAN communication errors
power supply or ground interruptions
ABS/EBS hybrid system malfunctions

Most codes are read using a diagnostic tool such as WABCO Toolbox, Knorr EBS Diagnostica, Jaltest, Texa, Launch X431 or OEM software.

📚 Common EBS Error Code Categories

1xx – Wheel Speed Sensor Errors (open circuit, short circuit, incorrect air gap, no signal)
2xx – EBS Modulator Valve Issues (coil error, power loss, stuck valve, pressure deviation)
3xx – Power Supply / Ground Problems (low voltage, high voltage, unstable supply)
4xx – CAN Communication Errors (lost signal to ECU, trailer EBS offline, tractor-trailer mismatch)
5xx – Brake Pressure Sensor Faults
6xx – ECU Internal Errors (memory error, overheating, software fault)

These categories are consistent across most truck brands including Mercedes, Volvo, Scania, MAN, Renault, DAF and Iveco.

🔎 EBS Fault Code Examples (WABCO + Knorr)

Code	Meaning
WABCO 01276	Rear left wheel speed sensor – no signal
WABCO 4331	Modulator valve – voltage low
Knorr 3F10	CAN communication fault with ABS block
Knorr 5D41	Brake pressure sensor – out of range
WABCO 4212	ECU internal memory error

🧮 Quick EBS Code Lookup Tool

Type your EBS code to display a quick explanation.

EBS Fault Code Decoder

Enter EBS Code: Explanation:

🛠 Troubleshooting Steps

Check wheel speed sensor cables and connectors
Measure modulator coil resistance
Verify 24V supply and chassis ground
Inspect CAN wiring for corrosion or breaks
Confirm correct sensor air gap (0.6–1.1 mm typical)
Run full ECU scan with WABCO/Knorr tools

🏁 Conclusion

EBS fault codes help technicians quickly identify braking system problems in trucks and semi trailers. Understanding the error groupings and knowing how to interpret common codes significantly speeds up diagnostic and repair work, improving fleet uptime and safety.

🛠️ Technical Insights

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