U0409moderate severityNetwork
Invalid Data Received From Body Control Module A
on 2013 Cadillac Escalade 6.2L V8 · 4WD
What this code means
The network is receiving corrupted data from body control module A. This can lead to faulty operation of body-related systems.
Symptoms
- Body electronics malfunction
- Dash warning lights
- Erratic accessory operation
Common causes
- Faulty body control module A
- Bus wiring or connector fault
- Corroded or loose connectors
- Software or programming error
Diagnostic steps
- Scan all modules for codes
- Check power and ground to BCM A
- Inspect data bus wiring and connectors
- Review BCM A live data 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.
Other Network codes on this vehicle
U0001
High Speed CAN Communication Bus
U0002
High Speed CAN Communication Bus Performance
U0003
High Speed CAN Communication Bus (+) Open
U0004
High Speed CAN Communication Bus (+) Low
U0005
High Speed CAN Communication Bus (+) High
U0006
High Speed CAN Communication Bus (-) Open
U0007
High Speed CAN Communication Bus (-) Low
U0008
High Speed CAN Communication Bus (-) High
U0009
High Speed CAN Communication Bus Shorted Together
U0010
Medium Speed CAN Communication Bus