U3006 Control Module Input Power Fault
Diagnostic trouble code U3006 indicates a fault in the primary power supply (battery or ignition voltage) to a specific control module. According to SAE J2012 and technical manuals, this code is set when the affected module detects that its supply voltage has dropped below or exceeded normal operating thresholds. This network DTC is triggered by an interruption, brown-out, or short circuit in the module's main power line, preventing the module from functioning correctly or communicating over the vehicle's CAN bus.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Weak or faulty vehicle battery
- Corroded or loose battery terminals
- Blown fuse or defective power relay for the control module
- Open or short-to-ground in the power supply wiring
- Damaged, bent, or corroded pins at the control module connector
- Internal failure of the electronic control module
3. Symptoms You Will Notice
- Check Engine Light or other warning lights illuminated
- Module-specific functions inoperative (e.g., ABS, transmission, body controls)
4. Step-by-Step Diagnosis
Check battery voltage and condition; charge or replace if necessary.
Inspect and clean battery terminals and cable connections.
Locate and test the fuse and relay for the affected module.
Visually inspect the module's power wiring for damage or shorts.
Check the module connector for bent, corroded, or loose pins.
If all else is okay, suspect a failed control module and test or replace it.
5. Frequently Asked Questions
Is it safe to drive?▼
No, driving with code U3006 is not recommended. The affected module may lose power, causing critical systems to fail or behave unpredictably, which can lead to a safety hazard.
How much does it cost to fix?▼
Repair costs vary widely: from $20 for a blown fuse to $200 for battery or wiring repairs, and up to $500–$1,000+ for module replacement including labor.