U0206

Code

Generic U — Network/User

Lost Communication With Folding Top Control Module

Brand: Generic

Type: U — Network/User

Views: UK: 24 EN: 58 RU: 32

AI status

Completed

ready

Completed 100%

Page language: EN

Folding top will not open or close using switches or remote
Instrument cluster or message center displays roof/convertible system error or 'service top' message
Related features disabled (interlocks, seat/roof move features)
No module response when queried with a scan tool
Intermittent operation or only manual override works

Connect a diagnostic scan tool and verify U0206 and any other network codes (U0100, U0142, etc.)
Attempt to communicate with the Folding Top Control Module using scanner; note if module appears in network list
Record module bus messages with CAN/LIN data by viewing network data or capture with a scope/sniffer
Inspect fuses and relays for the roof module and measure supply voltage at the module connector
Visually inspect module connector and wiring for corrosion, bent pins, water intrusion, chafing, or damage
Check battery state-of-charge and charging system; retest with battery fully charged

Module supply voltage: battery voltage at module pin (nominal ~12 V with ignition on)
Module ground continuity:
CAN bus voltages (recessive): CAN H ~2.5 V, CAN L ~2.5 V; dominant states show ~3.5 V and ~1.5 V respectively
Bus termination: approx. 60 ohms between CAN H and CAN L
Presence/absence of expected messages: convertible_top_status, roof_cmd, latch_status (message IDs vary by manufacturer)
Data rate: confirm expected CAN bus speed (commonly 250 kb/s or 500 kb/s) and that module is on correct network

Retrieve freeze frame and all current/recorded codes. Note related network codes.
Try to communicate with the Folding Top Control Module with a scan tool. If responsive, review live data and fault logs; clear code and re-check if it returns.
Verify battery voltage is adequate (≥12.4 V resting, ≥13.5 V charging with engine running) and inspect battery connections.
Check fuses/relays supplying the folding top module. Replace any blown fuses and retest communication.
Visually inspect the module connectors and harness for corrosion, moisture, damaged pins, or loose terminals. Repair as needed and retest.
With ignition on, backprobe module power and ground pins to confirm stable supply and good ground. Repair wiring if readings are out of range.
Use a CAN/LIN bus scanner or oscilloscope to monitor traffic. Confirm the module sends/receives messages. If no messages, isolate by disconnecting nearby nodes or short sections to find bus fault.
Measure CAN H/L voltages and bus termination. Repair short or open on the bus wiring if voltages or resistance are incorrect.
If harness and bus are good, consider swapping with a known-good folding top module (if available) or reflashing/reprogramming module software per service information.
After repairs, clear codes and verify proper operation of folding top through several cycles. Check for return of the code and re-run network checks.

Blown fuse or disconnected power/ground to the folding top module
Damaged connector or wiring harness at the folding top module (moisture/abrasion)
CAN bus fault (short, open, missing termination) causing no messages from that module
Failed folding top control module