Lost Communication with EGR Valve B Module
The U010B code indicates that the powertrain control module (PCM) or master control module has lost communication on the data bus (typically CAN) with the exhaust gas recirculation (EGR) valve 'B' control module. This module manages the operation of a specific EGR valve in dual or multiple EGR configurations. The communication loss can be caused by network wiring faults, power or ground issues, or internal failure of the EGR module, preventing the PCM from receiving feedback or sending positioning commands.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Open, shorted, or high-resistance CAN/LIN bus wiring to the EGR 'B' module
- Corroded, bent, or disconnected connector at the EGR 'B' module
- Internal failure of the integrated control module within the EGR 'B' valve
- Open or interrupted power (B+) or ground (GND) circuit to the EGR 'B' module
- Blown fuse supplying the EGR 'B' module (if applicable per wiring diagram)
- Faulty PCM/ECM or communication bus termination module
3. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance or limp mode
- Rough idle or hesitation
- Increased emissions
4. Step-by-Step Diagnosis
Scan for other related codes and check freeze frame data
Inspect the EGR 'B' module connector for corrosion, damage, or looseness
Test power and ground circuits at the EGR 'B' module with a multimeter
Check the CAN bus wiring for continuity, shorts, and proper resistance (typically 60 ohms)
Verify the EGR 'B' module fuse (if equipped) and replace if blown
If all circuits are intact, replace the EGR 'B' valve/module and clear codes
5. Frequently Asked Questions
Is it safe to drive?▼
It is not recommended to drive with this code, as it can cause drivability issues and increased emissions. The vehicle may enter limp mode, reducing power and potentially creating unsafe driving conditions.
How much does it cost to fix?▼
Repair costs typically range from $150 to $600, depending on the cause. A simple wiring repair may cost $150-$300, while replacing the EGR valve/module can run $300-$600 including parts and labor.