U0237
NetworkModule Communicationlow severityLost Communication With EC/Auto Dimming Mirror
What U0237 Means
The vehicle lost communication with the electrochromic auto-dimming mirror. Automatic mirror dimming and related features may fail.
Symptoms
- Mirror not auto-dimming
- Compass or features not working
- Warning message
Common Causes
- Faulty auto-dimming mirror
- Wiring or connector fault
- Blown fuse or lost power/ground
- Damaged bus wiring
Diagnostic Steps
- Scan for communication codes
- Check mirror power and ground
- Inspect headliner connectors
- Test bus wiring continuity
🔌 Don't have a code reader?
Any of these will read and clear this code — pick by how deep you want to go.
Budget handheld~$40
ANCEL AD410 →
No-phone-needed handheld — reads, clears, live data, freeze frame.
✓ ANCEL official store
Serious DIY~$100
BlueDriver Pro →
Enhanced codes (ABS, airbag, TPMS) plus repair reports.
SHOP FAVORITEShop-grade tablet~$300
Autel MaxiCOM MK808S →
Bidirectional tests, service resets, all systems.
✓ Autel official store
Pro diagnostics$1,500+
Autel MaxiSys MS906 Pro →
Full-system pro platform — topology mapping, ECU coding, the works.
✓ Autel official store
As an Amazon Associate and Autel/ANCEL partner, OLP earns from qualifying purchases — how we link. This never changes the specs we publish.
Community Confirmed Fixes
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