P0478 Dodge Code - High Voltage On The Engine Brake Driver
Quick Answer
The P0478 diagnostic trouble code (DTC) for Dodge vehicles indicates that there is a high voltage condition detected on the engine brake driver circuit. Common causes include Faulty engine brake driver circuit, Short circuit in the engine brake driver wiring, Malfunctioning engine brake switch. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P0478 Dodge indicates High Voltage On The Engine Brake Driver.
- Common causes
- Common causes include Faulty engine brake driver circuit, Short circuit in the engine brake driver wiring, Malfunctioning engine brake switch.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
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 P0478 Dodge Description
The P0478 diagnostic trouble code (DTC) for Dodge vehicles indicates that there is a high voltage condition detected on the engine brake driver circuit. The engine brake driver is responsible for controlling the operation of the engine brake, which helps to slow down the vehicle by reducing engine power. When this code is triggered, it means that the voltage on the engine brake driver circuit is exceeding the specified parameters, potentially causing issues with the engine brake system.
Common Causes of P0478 Dodge
- Faulty engine brake driver circuit
- Short circuit in the engine brake driver wiring
- Malfunctioning engine brake switch
- Corrosion or damage to the engine brake driver connector
- Issues with the engine brake control module
Symptoms of P0478 Dodge
- Erratic engine braking behavior
- Engine brake not engaging
- Reduced engine braking power
- Illuminated Check Engine Light
- Decreased fuel efficiency
How to Fix P0478 Dodge
- Begin by diagnosing the root cause of the high voltage condition on the engine brake driver circuit using a scan tool.
- Inspect the engine brake driver circuit, wiring, and connectors for any damage or corrosion, repairing or replacing as necessary.
- Test the engine brake switch and control module for proper functionality and replace if faulty.
- Clear the DTC and reset the engine control module to see if the issue has been resolved.
- Test drive the vehicle to ensure that the engine brake system is operating correctly.
Cost to Fix P0478 Dodge
The typical repair costs for addressing the P0478 code can vary depending on the specific cause of the issue and the extent of the repairs needed. In general, the cost of parts for this repair can range from $100 to $300, while labor costs can add another $100 to $200 to the total bill. Keep in mind that diagnostic time and labor rates at auto repair shops can vary, so it's advisable to check with local shops for a more accurate estimate.
When is the Code Detected?
Need more information about the P0478 Dodge code?
Need more information on how to fix the P0478 Dodge code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0478 Dodge code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0478 Dodge Code
No Frequently Asked Questions about P0478 Dodge Code found.
Discuss the causes and fixes for P0478 Dodge OBDII Code
Code P0478 Dodge 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.