U0933
NetworkModule Communicationlow severityLost Communication With Cellular/Telematics Module
What U0933 Means
The vehicle's network has lost communication with the telematics or connectivity module. This typically disables emergency calling, remote services, and connected features.
Symptoms
- Loss of connected services
- Telematics warning message
- Emergency call feature inoperative
Common Causes
- Faulty telematics module
- Blown fuse or bad power supply to module
- Damaged CAN bus wiring or connectors
- Corroded or loose module ground
Diagnostic Steps
- Scan all modules for related U-codes
- Check power and ground at telematics module
- Inspect CAN bus wiring for damage
- Verify module communication with scan tool
🔌 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.
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