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B3889 Buick Code - Trailer Brake Lamps

- Code Popularity: 307 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC B3889 Buick?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Faulty Trailer Brake Lamps
  • Trailer Brake Lamps harness is open or shorted
  • Trailer Brake Lamps circuit poor electrical connection
  • Faulty Trailer Lighting Control Module
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How to Fix the DTC B3889 Buick?

Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.

Code Tech Notes

B3889 02 Trailer Brake Lamps Circuit Short to Ground
B3889 04 Trailer Brake Lamps Circuit Open

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3889 Buick code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

Code B3889 Buick Description

The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The Body Control Module (BCM) provides a low reference signal and a 5 V reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM applies battery voltage to the center high mounted stop lamp control circuit and Trailer Lighting Control Module. The Trailer Lighting Control Module responds by applying battery voltage to the trailer stop lamp control circuit illuminating the trailer stop lamps.

OBDII Code B3889 Buick - Trailer Brake Lamps - AutoCodes.com
B3889 Buick Code - Trailer Brake Lamps

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Code B3889 Buick comments

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