B278A Code - Short to GND in Immobiliser System Power Source Circuit
Quick Answer
The diagnostic trouble code B278A indicates a short to ground in the immobiliser system power source circuit. Common causes include Damaged wiring or connectors in the power source circuit, Faulty immobiliser system control module, Corrosion in the power source circuit. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- B278A indicates Short to GND in Immobiliser System Power Source Circuit.
- Common causes
- Common causes include Damaged wiring or connectors in the power source circuit, Faulty immobiliser system control module, Corrosion in the power source circuit.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code B278A Description
The diagnostic trouble code B278A indicates a short to ground in the immobiliser system power source circuit. The immobiliser system is a security feature in modern vehicles that prevents the engine from starting unless the correct key or key fob is used. This system relies on a power source circuit to function properly. A short to ground in this circuit can potentially disrupt the power supply to the immobiliser system, causing issues with starting the vehicle or even preventing it from starting altogether.
Common Causes of B278A
- Damaged wiring or connectors in the power source circuit
- Faulty immobiliser system control module
- Corrosion in the power source circuit
- Short circuit in the immobiliser system wiring
- Malfunctioning key or key fob
Symptoms of B278A
- Engine cranks but does not start
- Engine starts but immediately stalls
- Immobiliser warning light illuminated on the dashboard
- Inability to deactivate the vehicle's immobiliser system
- Malfunctioning key fob or key recognition issues
How to Fix B278A
- Begin by inspecting the wiring and connectors in the immobiliser system power source circuit for any signs of damage or corrosion.
- Test the immobiliser system control module to determine if it is functioning correctly or needs to be replaced.
- Check for any short circuits in the immobiliser system wiring and repair as necessary.
- Verify the functionality of the key or key fob and replace if faulty.
- Clear the diagnostic trouble code from the vehicle's computer and test the immobiliser system to ensure proper operation.
Cost to Fix B278A
The typical repair costs for addressing a short to ground in the immobiliser system power source circuit can vary depending on the specific cause of the issue and the make and model of the vehicle. In general, the parts required for this repair, such as wiring, connectors, or a new immobiliser system control module, could range from $100 to $500. Labor costs can add an additional $100 to $300, depending on the complexity of the repair and the rates charged by the auto repair shop.
Need more information about the B278A code?
Need more information on how to fix the B278A code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the B278A code diagnosed by a professional: Find a repair shop in your area
Code B278A Information for Specific Makes
- B278A Lexus — Short to GND in Immobiliser System Power Source Circuit
- B278A Nissan — Electric Compressor Low Voltage
- B278A Scion — Short to GND in Immobiliser System Power Source Circuit
- B278A Toyota — Short to GND in Immobiliser System Power Source Circuit
Frequently Asked Questions about B278A Code
1. What are the common symptoms of OBDII code B278A (Short to GND in Immobiliser System Power Source Circuit)?
- Common symptoms include difficulty starting the vehicle, intermittent stalling, and the immobilizer system malfunctioning.
2. What are the possible causes of OBDII code B278A?
- Possible causes include damaged wiring in the immobilizer system circuit, a faulty immobilizer control module, or a short to ground in the power source circuit.
3. How can I diagnose OBDII code B278A?
- Diagnosing this code involves performing a thorough inspection of the wiring in the immobilizer system circuit, testing the immobilizer control module, and checking for any shorts to ground in the power source circuit.
4. Can I still drive my vehicle with OBDII code B278A present?
- It is not recommended to drive the vehicle with this code present, as it may lead to issues with starting the engine or the immobilizer system functioning properly.
5. How can I repair OBDII code B278A?
- Repairing this code typically involves repairing or replacing damaged wiring in the immobilizer system circuit, replacing the immobilizer control module if necessary, and addressing any shorts to ground in the power source circuit.
6. Is it safe to reset the OBDII code B278A with a diagnostic tool?
- It is safe to reset the code temporarily to see if it reoccurs after making repairs. However, it is crucial to address the underlying issue causing the code to prevent further problems.
7. Can a DIYer fix OBDII code B278A at home?
- While some basic troubleshooting steps can be performed at home, diagnosing and repairing OBDII code B278A may require advanced knowledge and tools. It is recommended to seek professional help for proper diagnosis and repair.
8. How much does it cost to repair OBDII code B278A?
- The cost of repairing this code can vary depending on the extent of the issue and the specific repairs needed. It is advisable to obtain quotes from automotive professionals for an accurate estimate.
9. Will OBDII code B278A cause a vehicle to fail an emissions test?
- Yes, OBDII code B278A can cause a vehicle to fail an emissions test due to the potential impact on the immobilizer system, which is an essential component for proper vehicle operation.
10. How long does it take to repair OBDII code B278A?
- The repair time for OBDII code B278A can vary based on the complexity of the issue and the availability of parts. It is best to consult with a mechanic to get an estimated timeframe for the repair.
Discuss the causes and fixes for B278A OBDII Code
Code B278A comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.