Skoda Octavia 2010 facelift: erori G85 după instalare casetă direcție Gen 2

madalin2401 wrote:

Bună ziua, am probleme cu o Skoda Octavia facelift din 2010. Am instalat caseta de direcție Gen 2, am instalat un computer de volan cu un...G85senzor, dar tot nu vedeG85senzor și tot am aceste erori @...

Initial assessment of available information
- Vehicle: Skoda Octavia II FL (1Z), MY 2010 (PQ35 platform).
- Retrofit performed: Gen2 electromechanical steering rack installed + a steering column control module (“steering wheel computer”) that supposedly includes/works with G85 (steering angle sensor).
- Complaint: The car “does not see” the G85 and keeps logging faults. Typical DTCs in this situation are 00778 (G85: No Signal/Communication) and 02546 (Steering Limit Stop Not Initialized).

Direct answer to the question
On a 2010 Octavia FL, a Gen2 rack swap will only work reliably if:
- The car’s electronics know where the G85 lives (in the steering column/slip ring module vs. in the rack) and are coded accordingly.
- The rack ECU (J500) is powered correctly (KL30, KL31, and—crucially on many Gen2 racks—KL15 ignition feed), is visible in the CAN Gateway, and has its limit stops learned.
- The ABS/ESP module (J104) can see a valid, calibrated G85 value via the expected source and accepts Basic Settings without other active DTCs.

If any of the three is wrong (wrong SCCM variant, missing KL15 at the rack, wrong coding/calibration order), the car will “not see” G85 and will repeatedly flag 00778/02546.

Detailed problem analysis
1) Architecture and “where is G85?”
- PQ35 cars came in two flavors:
- G85 in the steering column (behind the slip ring, managed by the Steering Column Control Module/SCCM: 1K0 953 549 xx). In this case, ABS reads G85 over CAN from the SCCM.
- G85 function handled differently (certain racks/years). Your 2010 Octavia FL typically expects G85 from the column/SCCM. If you fitted an SCCM variant that reports “Steering angle sensor: No,” ABS will never see G85.
- Action:
- Read the part number and identification of your SCCM in 16-Steering Wheel Electronics (example: 1K0 953 549 BD/CH/CK/…).
- In VCDS → 16 → Adv. ID/Adv. Measuring Values: check if there is a “Steering angle” live value AND if the label for that SCCM indicates “Steering Angle Sensor: Yes.” If the value changes smoothly with wheel rotation, the sensor and SCCM are OK.
- If no angle appears in 16 but you do see wheel buttons/cruise inputs, your SCCM variant likely does not include/serve G85. You need a compatible SCCM (suffix matters!) that supports G85 for your car.

2) Gen2 rack power and wake-up (very common pitfall)
- Many Gen2 TRW racks require an ignition-switched +12 V (Terminal 15) in addition to the heavy battery feed (KL30) and ground (KL31). Later racks can wake via CAN only; Gen2 often cannot.
- If KL15 is missing, J500 stays asleep or half-awake → no comms with 44-Steering Assist, Gateway shows intermittent/no 44, ABS cannot complete calibrations, and G85-related procedures fail.
- Action (verify with a multimeter, not just continuity):
- At the rack’s connectors (consult your exact wiring diagram/erWin for pinout), verify:
- KL30: battery voltage within 0.5 V of the battery at load.
- KL31: voltage drop < 0.2 V to chassis during a steering assist demand (turn wheel at idle).
- KL15: +12 V present with ignition ON.
- CAN-H/L: with ignition ON, ≈2.5–3.5 V (H) and ≈2.5–1.5 V (L) and ≈60 Ω across the pair with the network powered down and a single segment connected.
- If KL15 is missing in your harness, run a fused ignition-switched feed to the correct rack pin (per factory diagram). Do not guess pin numbers—use the OEM schematic.

3) Coding and Gateway configuration
- 19-CAN Gateway → Installation List must include 44-Steering Assist. If 44 is missing or shows “No Communication,” ABS will not accept G85/Basic Settings.
- 16-SCCM long coding must match your equipment (MFSW, CC, etc.) AND the presence/location of G85.
- 03-ABS long coding: some ABS variants have bits that define source/availability of G85; use the coding helper and confirmed label file for your exact ABS (MK60/MK60EC1). Incorrect coding can block Basic Settings.
- Action:
- Perform a full Auto-Scan, save it, then correct Gateway installation and module codings based on your PR-codes and hardware.

4) Correct order of calibrations (two separate things)
- Limit stop adaptation for the rack (module 44-J500):
- 44-Steering Assist → Security Access (commonly 40168) → Basic Settings → select “Steering Limit Stop” (often group 060) → follow prompts: full left stop → full right stop → center → confirm.
- If this fails with 02546, confirm power/KL15 and that 44 is coded properly and stable on the CAN.
- Steering Angle Sensor (G85) Basic Setting (module 03-ABS):
- Prereqs: no other ABS/steering DTCs active; battery >12.2–12.5 V; wheels straight; engine running.
- 03-ABS → Security Access (for many MK60/MK60EC1 it is 40168) → Basic Settings → “Steering Angle Sensor” (often group 060).
- Some variants require a short drive: turn wheel 1 turn left/right, then drive straight <20 km/h, stop with wheels straight, perform Basic Setting, confirm 0.0° ±0.5°.
- If either step says “Not possible,” fix the underlying DTCs first (including 02546 at 44).

5) Verifying that G85 exists and the ABS can see it
- Quick triage with live data:
- 16-SCCM: steering angle value must change smoothly with wheel rotation.
- 44-Steering Assist: Measuring Blocks/Adv. Measuring Values: angle and torque should change when turning.
- 03-ABS: Measuring Blocks group 004 field 1 (typical on MK60/EC1) should show a plausible steering angle once everything is calibrated.
- Scenarios:
- Angle present in 16, absent in 03: coding/Basic Setting problem at ABS side.
- Angle absent in 16: wrong SCCM variant, damaged slip ring/wickelfeder, or no G85 hardware.
- Angle present but jumps/flatlines near ±540–720°: slip ring not centered → out-of-range → redo mechanical centering and then Basic Settings.

6) Hardware compatibility details that often bite
- SCCM part family 1K0 953 549:
- Certain suffixes (e.g., CF) are “Steering Angle Sensor: No”; others (e.g., BD/CH/CK etc.) are “Yes.” Mixing them without recoding/replacement causes 00778 no matter what you do in ABS.
- If you retrofitted MFSW and picked a “Highline” SCCM for buttons but that unit has “No” for SAS, you must either change SCCM to a “Yes” unit or add the separate SAS that matches your column—mixing these is not plug-and-play.
- Used racks:
- Usually they carry their parameter set (assist curve) and work, but some need parameterization (ODIS/VCP dataset) to clear coding faults. If 44 shows permanent “Incorrectly Coded/Parameter set missing,” G85/ABS calibrations will not complete. Solve parameterization first.
- Wiring at the column:
- If the slip ring and SCCM were swapped, poor contact at the multiway connector or a damaged wickelfeder track will produce intermittent G85 and false “No Comm.”

7) Electrical verification at the column (if 16 shows no angle)
- Confirm SCCM powers/grounds (use a headlamp bulb as a load tester if voltages look “OK” on a DMM).
- Check that the clockspring is centered mechanically (install position typically: center detent, equal turns to each side; lock with shipping pin before installation).
- If available, scope the G85 internal channels (many are dual-redundant hall or optical; patterns should be consistent and monotonic). If the SCCM stores 00778 locally and no angle value moves, the G85 element or internal SCCM ADC path is faulty → replace SCCM or the G85 submodule (depending on variant).

Current information and trends
- On PQ35 platforms doing Gen2↔Gen3 swaps, the most frequent root causes are missing KL15 at the rack and using an SCCM variant that doesn’t provide G85 to ABS over CAN. Both are solved by wiring correction and correct SCCM selection/coding.
- Newer diagnostic suites (recent VCDS/ODIS) add guided functions that validate prerequisites before allowing Basic Settings—use an updated tool to avoid blind attempts.

Supporting explanations and details
- Why 02546 appears: After rack replacement the controller will not provide valid angle/assist integration to ABS until it learns physical end stops; ABS refuses to accept G85 Basic Setting if steering assist is not healthy.
- Why 00778 appears: ABS expects a valid, calibrated G85 value. If SCCM reports “No SAS,” or CAN messages are missing, or the value is outside limits due to miscentered clockspring, ABS flags 00778.

Ethical and legal aspects
- Airbag/steering work is safety-critical. Always disconnect the battery and follow OEM procedures when removing the wheel/airbag. A miscentered clockspring can deploy faults or damage SRS components.

Practical guidelines (step-by-step you can follow today)
1) Full Auto-Scan and share it:
- Addresses 03, 16, 19, 44 at minimum. Note software part numbers, codings, and all DTCs.
2) Check live angle in modules:
- 16: Does “Steering angle” change smoothly?
- 44: Do angle/torque values move?
- 03: Is an angle shown in measuring blocks?
3) Fix rack power/comms first:
- Verify KL30/KL31/KL15 and CAN at the rack. Correct wiring per factory diagram if KL15 is absent.
- Ensure 44 is present and stable in 19-Gateway Installation List.
4) Perform calibrations in this order:
- 44: Security access (commonly 40168) → Basic Settings → Steering Limit Stop.
- 03: Security access (often 40168) → Basic Settings → Steering Angle Sensor. Follow the drive/straight-line prerequisites if requested.
5) If 16 shows no angle:
- Confirm SCCM variant supports G85 (“Steering Angle Sensor: Yes”). If not, source the correct SCCM or the correct G85 module for your column.
6) Only after zero DTCs remain, road test and re-check for stored faults.

Possible disclaimers or additional notes
- Security access codes and group numbers vary with ABS generation. If your Basic Settings screen labels differ, use the label that mentions “Steering Angle Sensor” and “Limit Stop.”
- Avoid guessing pinouts; always use the exact wiring diagram for your VIN to place KL15 on the correct rack pin.

Suggestions for further research
- Verify your ABS generation (e.g., MK60EC1) and consult the matching Basic Settings procedure.
- Confirm SCCM suffix capabilities (Ross-Tech label/scan will show whether “Steering Angle Sensor: Yes/No”).
- If 44 reports parameterization errors, you may need ODIS/VCP to load the correct dataset.

Brief summary
- Make sure the rack ECU is fully alive on CAN (including KL15).
- Use an SCCM that actually provides G85 and code it correctly.
- Do limit-stop adaptation in 44, then do G85 Basic Setting in 03 with all other DTCs cleared.
- If 16 never shows an angle, you have the wrong SCCM/G85 hardware or a faulty clockspring/sensor.

Questions for the user (needed to pinpoint the fix)
- Please post a complete VCDS Auto-Scan (Addresses 03, 16, 19, 44).
- Exact DTC numbers you see (e.g., 00778, 02546, 01309, etc.).
- Part numbers:
- Steering rack you installed (e.g., 1K2/1K1…/1Z1… plus suffix).
- SCCM (1K0 953 549 xx suffix).
- Slip ring/clockspring part number if separate.
- Does 16-Steering Wheel show a live steering angle that changes when you turn the wheel?
- Have you verified KL15 is present at the rack connector with ignition ON? If yes, what voltage do you measure under load?
- Is 44-Steering Assist present and stable in 19-Gateway Installation List?

Provide these, and I will map the exact pin/wiring checks for your variant and the correct coding/calibration sequence for your ABS and rack.