B3903 Saturn Code - Stop Lamp Relay Circuit Short
Quick Answer
The Body Control Module (BCM) supplies voltage to the Center High Mount Stop Lamp (CHMSL) and the Powertrain Control Module (PCM) when the stop lamps are active. Common causes include Faulty Stop Lamp Relay, Stop Lamp Relay harness is open or shorted, Stop Lamp 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
- B3903 Saturn indicates Stop Lamp Relay Circuit Short.
- Common causes
- Common causes include Faulty Stop Lamp Relay, Stop Lamp Relay harness is open or shorted, Stop Lamp 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 B3903 Saturn Description
What are the Possible Causes of the DTC B3903 Saturn?
- Faulty Stop Lamp Relay
- Stop Lamp Relay harness is open or shorted
- Stop Lamp Relay circuit poor electrical connection
- Faulty Body Control Module (BCM)
How to Fix the DTC B3903 Saturn?
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.
Code Tech Notes
B3903 05 Stop Lamp Relay Circuit Short to Battery or Open
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the B3903 Saturn 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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Need Help with the Code?
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Frequently Asked Questions about B3903 Saturn Code
1. What are the common symptoms of OBDII code B3903 in a Saturn related to the Stop Lamp Relay Circuit Short?
The common symptoms include non-functioning brake lights, illuminated brake warning light on the dashboard, and possible issues with the vehicle's cruise control system.
2. What typically causes the OBDII code B3903 related to the Stop Lamp Relay Circuit Short in a Saturn?
The code is usually triggered by a short circuit in the wiring of the stop lamp relay circuit, a faulty stop lamp switch, or a malfunctioning relay itself.
3. How can I diagnose the OBDII code B3903 in my Saturn for the Stop Lamp Relay Circuit Short?
To diagnose the issue, you should check the wiring harness and connections for any visible damage, test the stop lamp switch for proper functionality, and verify the relay's operation using a multimeter.
4. Are there any DIY repair tips for fixing the Stop Lamp Relay Circuit Short issue in a Saturn triggering the B3903 code?
DIY repair tips include checking and repairing any damaged wiring, replacing a faulty stop lamp switch, or swapping out a malfunctioning relay with a new one to resolve the circuit short.
5. Can the OBDII code B3903 related to the Stop Lamp Relay Circuit Short in a Saturn cause any safety concerns?
Yes, the code can pose safety concerns as non-functioning brake lights may lead to rear-end collisions due to the lack of proper warning signals to vehicles behind you.
6. Is it safe to continue driving my Saturn with the OBDII code B3903 active for the Stop Lamp Relay Circuit Short?
It is not recommended to drive the vehicle with this code active, as it indicates a potential issue with the brake lights that can compromise the safety of your driving and that of others on the road.
7. Will resetting the OBDII code B3903 related to the Stop Lamp Relay Circuit Short make the issue go away permanently?
Resetting the code without addressing the underlying cause will not fix the problem permanently. It is crucial to diagnose and repair the root cause to prevent the code from reoccurring.
8. How much can I expect to pay for professional repairs for the OBDII code B3903 in a Saturn due to the Stop Lamp Relay Circuit Short?
The cost of professional repairs can vary depending on the exact cause of the issue, but it may range from $100 to $300, including parts and labor.
9. Can a mechanic easily fix the OBDII code B3903 related to the Stop Lamp Relay Circuit Short in a Saturn?
Yes, a qualified mechanic should be able to diagnose and repair the issue efficiently, especially if they have experience working on Saturn vehicles and electrical systems.
10. How urgent is it to address the OBDII code B3903 for the Stop Lamp Relay Circuit Short in a Saturn?
It is important to address this code promptly to ensure the proper functioning of the brake lights and maintain road safety for you and other drivers.
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