U0515: Invalid RFA Module Data
The U0515 code indicates that a control module (typically the ECM/PCM or BCM) has received invalid, inconsistent, or out-of-range data from the Remote Function Actuation (RFA) module over the CAN bus. The RFA module manages keyless entry, alarm, immobilizer, and tire pressure monitoring (TPMS). Invalid data prevents verification of these functions, potentially disabling them.
1. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.
2. Most Common Causes
- Faulty RFA module with corrupted software or hardware failure
- CAN bus issues such as short circuits, open circuits, or electrical interference
- Damaged wiring or connectors between the RFA module and the data bus
- Low battery voltage or voltage spikes corrupting data transmission
- Incorrect programming or software incompatibility after module replacement or update
3. Symptoms You Will Notice
- Keyless entry not working
- Alarm system malfunctions
- Immobilizer preventing engine start
- TPMS warning light on
- Check Engine Light or other warning lights illuminated
4. Step-by-Step Diagnosis
Scan all modules for related codes and check freeze frame data
Inspect battery voltage and charging system; ensure stable power
Visually check CAN bus wiring and connectors for damage or corrosion
Test CAN bus continuity and resistance at the RFA module connector
Check for software updates or reflash the RFA module if needed
If all else fails, replace the RFA module and reprogram it
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, but some features like keyless entry, alarm, and TPMS may be disabled. The vehicle may still run, but starting could be affected if the immobilizer is involved. Have it diagnosed soon.
How much does it cost to fix?▼
Diagnosis typically $100-$150. If the RFA module needs replacement, parts and labor can range from $300 to $800, depending on the vehicle and programming requirements.