Rear Left Interior Light Timer Circuit Malfunction
The B0169 code means the vehicle's onboard diagnostic system has detected: Rear Left Interior Light Timer Circuit Malfunction. This is a low severity code.
- Keep driving?
- Yes, but fix soon
- DIY difficulty
- moderate
- Estimated cost
- $30 - $200 (parts and labor)
Basic scanners skip body codes entirely. BlueDriver reads airbag, HVAC, lighting, and BCM codes through your phone.
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Common Symptoms
- Interior lights do not turn off automatically
- Interior light timer not functioning
- Lights stay on with all doors closed
- Timer duration inconsistent
Probable Causes (Ranked by Likelihood)
- BCM interior light timer function failure Very High
- Faulty door ajar sensor input High
- Interior light relay stuck on Moderate
- BCM software glitch Low
Step-by-Step Diagnostic Procedure
-
Check BCM timer settings with scan tool
-
Verify all door ajar sensors
-
Test interior light relay
-
Perform BCM software update if available
Frequently Asked Questions
Why do interior lights stay on?
Usually a door ajar sensor telling the BCM a door is open, or a failed timer function in the BCM.
How long should interior lights stay on?
Most vehicles turn off interior lights after 10 to 20 minutes if a door ajar signal is present.
Will this drain my battery?
Yes, if interior lights remain on due to a timer fault, the battery can drain within hours.
Sources
This page is built from documented references. Verify against your own service info before repair work.
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