Ambient Light Sensor Circuit Range/Performance Problem
There's a problem with the ambient light sensor's signal.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The ambient light sensor reads the amount of light outside the vehicle and sends this info to the computer. If it senses too much or too little light, it can trigger this code.
What the computer is actually seeing
The computer expects a steady voltage reading from the sensor, typically between 0.5 to 4.5 volts, corresponding to light levels. A reading outside this range indicates a fault.
What a healthy reading looks like
Voltage should range from 0.5V (dark) to 4.5V (bright) under normal conditions.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the wiring and connectors for the ambient light sensor. Look for frays and corrosion.
- 22. Check sensor operation by measuring the voltage on the connector while covering and exposing the sensor. Expect voltages shifting between 0.5V and 4.5V.
- 33. If voltage readings are stable but out of range, replace the ambient light sensor. If readings are erratic, check for more wiring issues or consider a software update.
Common causes
- Faulty ambient light sensor
- Wiring issues in the sensor circuit
- Bad connector or corrosion
- Software glitches in the body control module
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, you can drive, but the automatic features linked to lighting may not function properly.
Will the code come back after clearing?
If the underlying issue isn't fixed, it likely will return.
Why does this code appear with others like B1272?
These codes often indicate issues with the same sensor circuit or related systems.
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