B2478 Chevrolet Code - Reverse Light Relay Shorted To Battery
Quick Answer
When Platform Zone Module (PZM) receives input that transaxle is in Reverse, PZM energizes reverse light relay which will turn on back-up lights. Common causes include Faulty Reverse Light Relay, Reverse Light Relay harness is open or shorted, Reverse Light Relay circuit poor electrical connection. 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
- B2478 Chevrolet indicates Reverse Light Relay Shorted To Battery.
- Common causes
- Common causes include Faulty Reverse Light Relay, Reverse Light Relay harness is open or shorted, Reverse Light Relay circuit poor electrical connection.
- 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.
Code B2478 Chevrolet Description
What are the Possible Causes of the DTC B2478 Chevrolet?
- Faulty Reverse Light Relay
- Reverse Light Relay harness is open or shorted
- Reverse Light Relay circuit poor electrical connection
- Faulty Platform Zone Module (PZM)
How to Fix the DTC B2478 Chevrolet?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B2478 Chevrolet code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about B2478 Chevrolet Code
1. What does the OBDII code B2478 mean on a Chevrolet?
B2478 indicates that the reverse light relay circuit is shorted to the battery, meaning there is an electrical fault causing the reverse light relay to receive power when it shouldn't.
2. What are the symptoms of code B2478 on a Chevrolet?
Common symptoms include reverse lights staying on constantly, reverse lights not turning on at all, or abnormal electrical behavior in the vehicle.
3. What causes the B2478 code to appear?
This code is typically caused by damaged wiring, a short circuit, a faulty reverse light relay, a malfunctioning backup light switch, or a grounded electrical connection.
4. Can I drive my Chevrolet with the B2478 code active?
Yes, but it is not recommended. Faulty reverse lights can create a safety hazard for other drivers and may result in a traffic violation.
5. How is the B2478 code diagnosed?
A technician will inspect the wiring and connectors in the reverse light circuit, test the reverse light relay, and check for shorts to the battery using a multimeter.
6. What repairs are needed to fix the B2478 code?
Repairs may include replacing damaged wiring, repairing a short circuit, replacing the reverse light relay, or replacing a faulty backup light switch.
7. How much does it cost to fix the B2478 code on a Chevrolet?
The cost depends on the nature of the issue but typically ranges from $50 to $200 for diagnosing and repairing the wiring or relay.
8. Can I fix the B2478 code myself?
If you have experience with electrical systems and a multimeter, you may be able to diagnose and repair the issue by inspecting and repairing the wiring or relay.
9. Will clearing the code B2478 fix the problem?
Clearing the code will temporarily remove it, but if the underlying issue isn’t addressed, the code will likely return.
10. How can I prevent the B2478 code from recurring?
Regularly inspect the wiring and connectors for wear or damage, and avoid exposure to moisture that can cause electrical shorts.
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