Lost Communication With Restraints Dimming Sensor Module
What does U0171 mean?
The U0171 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Restraints Dimming Sensor Module. This is a low severity code.
Common Symptoms
- Airbag warning light may illuminate
- Dashboard dimming function inoperative
- Automatic brightness control not working
- Headlight auto-dim feature disabled
- Interior lighting does not adjust automatically
Probable Causes (Ranked by Likelihood)
- Failed dimming sensor module on dashboard Very High
- Damaged wiring to sensor on windshield High
- Windshield replacement disrupted sensor connection Moderate
- Module software fault requiring update Low
Step-by-Step Diagnostic Procedure
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Check the light sensor on the dashboard near the windshield
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Inspect wiring from sensor to body control module
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Verify the sensor was reconnected after any windshield work
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Check for related body control module codes
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Test sensor response with a flashlight and scan tool live data
Frequently Asked Questions
Can I drive with code U0171?
Yes, safe to drive. The automatic dimming and brightness features will not work but you can manually adjust settings.
What causes U0171?
Often caused by a failed sensor or disrupted connection after a windshield replacement. The sensor is located near the top of the windshield.
Is U0171 expensive to fix?
Usually $100 to $350. If the sensor was just disconnected during windshield work, reconnecting it is often a quick and inexpensive fix.