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AutoCodes - Generic - B1A85

B1A85 Code - Ambient Light Sensor

- Code Popularity: 4,996 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
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What are the Possible Causes of the DTC B1A85?

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 Ambient Light Sensor
  • Ambient Light Sensor harness is open or shorted
  • Ambient Light Sensor circuit poor electrical connection
  • Faulty Steering Column Control Module (SCCM)
  • Faulty Body Control Module (BCM)
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How to Fix the DTC B1A85?

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

B1A85:11 Ambient Light Sensor Circuit Short To Ground
B1A85:13 Ambient Light Sensor Circuit Open

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1A85 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 B1A85 Description

The Steering Column Control Module (SCCM) sends voltage signals to the headlamp switch through the headlamp switch input circuits (off, parking lamps, headlamps, autolamps). At any given time, the headlamp switch routes one of the input circuits to ground, indicating the headlamp switch position to the SCCM .
The SCCM sends the status of the headlamp switch position to the Body Control Module (BCM) over the High Speed Controller Area Network (HS-CAN).
The autolamp feature is enabled when the BCM receives a message from the SCCM indicating the headlamp switch in the AUTOLAMPS ON position.
When the BCM enables the autolamps feature, the BCM monitors the light sensor input. The light sensor determines the amount of light based on the input received from the ambient lighting conditions. When the ambient level has reached a point (determined by the internal programming of the BCM ), the BCM provides voltage to the exterior lamps.
If the SCCM detects multiple or no active headlamp switch inputs, it sends a message to the BCM to indicate a fault with the headlamp switch input.

OBDII Code B1A85 - Ambient Light Sensor - AutoCodes.com
B1A85 Code - Ambient Light Sensor

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Code B1A85 comments

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