Code
U0429
Generic
U — Network/User
Invalid Data Received From Steering Column Control Module
Views:
UK: 25
EN: 81
RU: 25
AI status
Completed
Completed
100%
Causes
- Faulty Steering Column Control Module (SCCM)
- Damaged or corroded connector(s) at SCCM or other modules
- Open, shorted, or high-resistance wiring on the CAN/LIN bus
- Low or unstable supply voltage or poor ground at SCCM
- Bus termination or network impedance problem
- Software mismatch, corrupted calibration, or missing reflash on SCCM or receiving module
Symptoms
- Illumination of warning lamp(s) related to steering/ESC/airbag/ABS depending on network
- Loss or incorrect steering angle, torque, or column position data on scan tool
- Other modules reporting related U‑codes or communication faults
- Intermittent or persistent limp or degraded vehicle handling features
- Possible store of related freeze frame data and multiple communication codes
What to check
- Use a scan tool to read U0429 and any other U‑codes; record freeze frame and occurrence count
- Check for other modules with communication faults (compare module presence on network)
- Visually inspect SCCM connector and harness for corrosion, bent pins, heat damage, or chafe marks
- Check battery voltage and charging system; perform load test if voltage unstable
- Backprobe CAN (or LIN) lines at SCCM and a neighboring module to confirm signal presence
- Wiggle test harness and connectors while monitoring bus messages for intermittent dropouts
Signal parameters
- Communication bus: typically CAN (CAN-H and CAN-L) or vehicle-specific network protocol
- Expected idle voltage: ~2.5 V on each CAN line (nominal) and ~60–120 ohm total termination (vehicle-specific)
- Message content: steering angle, column position, torque request, checksum/CRC on message payload
- Message frequency: steering-angle messages typically 10–100 Hz (manufacturer-specific)
- Observe for bus errors/frames per second, error counters and lost frames in scan tool
Diagnostic algorithm
- Retrieve and document all related DTCs and freeze-frame data; note when code was set and driving conditions.
- Attempt to clear codes and perform short test drive to see if U0429 returns and under what conditions.
- Verify vehicle battery voltage and charging system; correct any low/unstable voltage issues.
- Visually inspect SCCM connector and wiring for damage, corrosion, or loose pins; repair or reseal as needed.
- Backprobe CAN-H and CAN-L at SCCM and at another module; confirm idle voltages and symmetry, and check for dominant/recessive transitions with a scope or capable scan tool.
- Use a scan tool to monitor SCCM messages (IDs) and payload; confirm expected message frequency and valid steering data when present.
- Perform wiggle test of harness and connectors while monitoring bus and codes to find intermittent faults.
- If wiring and connectors are good, check for software/calibration level; compare SCCM software version with manufacturer spec and apply updates or reflash if required.
- If SCCM fails to send valid messages after wiring and software verified, remove and bench-test or replace SCCM following manufacturer procedures; reprogram and code new module if required.
- After repairs, clear codes and re-evaluate on road; verify no related modules report communication faults and that steering data is present and plausible.
Likely causes
- SCCM failing and sending malformed messages
- CAN bus wires chafed/shorted to chassis or each other near steering column
- Poor pin contact or corroded connector at SCCM connector Cxxx
- Battery low or alternator ripple causing data errors during message transfer
- Missing or incorrect software calibration in SCCM after replacement or service
Fault status
Status
Module received invalid or corrupted steering-column data on the vehicle network; communication or SCCM data integrity fault detected.
Repair difficulty: Medium
Diagnostic time: 1.0-2.5 hours
Similar codes
Workshop Manuals
Available brands with manuals
2
AUDI 11
6-speed manual gearbox 0B1, front-wheel drive — Workshop Manual (Edition 05.2014)
Workshop ManualAudi A3 (1997) – 1.6L 4-cylinder (2‑valve) Engine Mechanical Components Service Manual (AEH, AKL, APF) – Edition 07.2002
Workshop ManualAUDI A3 (2004) Workshop Manual — 2.0L FSI Turbo (4‑cyl, 4‑valve) Engine, Mechanics — Edition 03.2017
Workshop ManualAudi A3 2004 — Electrical System (Workshop Manual, Edition 02.2018)
Workshop ManualAudi A4 / A4 Cabriolet – 4.2 l V8 (5‑valve, timing chains) – Workshop Manual (Mechanics) – Edition 04.2007
Workshop ManualAudi A4 / A4 Cabriolet — Auxiliary Heater Workshop Manual (Edition 08.2004)
Workshop ManualAudi A4 / A4 Cabriolet (1.8T 4‑cyl turbo) — Motronic Injection & Ignition System Service Manual (Edition 01.2015)
Workshop ManualAudi A8 (2003) — Electrical System Workshop Manual (Edition 08.2014)
Workshop ManualAudi Q4 e-tron (Type F4) - Self-study Programme SSP 685
Workshop ManualAudi Q8 (2018) — Electrical System Workshop Manual (Edition 05.2019)
Workshop ManualAudi Servicing Manual — 7‑Speed Dual Clutch Transmission 0CJ / 0CL / 0CK / 0DN / 0DP / 0HL (Edition 05.2018)
Workshop ManualLAND ROVER 3
Land Rover Defender 300Tdi — Workshop Manual (1996 model year)
Workshop ManualLand Rover Defender Workshop Manual Supplement & Body Repair Manual (1999 & 2002 MY)
Workshop ManualLand Rover Range Rover — Electrical Library (LRL 0453ENG, 2002)
Workshop ManualYour experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
