Hi guys I’m hoping for some advice. I’ve got an Active Roll Control fault on my Range Rover sport 2.7 2005. (Amber body roll light on display)

My gap tool shows U0428-86 invalid data from steering angle sensor. Invalid or missing message.

The gap tool live data for the steering sensor is showing it working fine.. I’ve swopped the sensor and still get the fault. I can clear the fault with the gap tool but it comes back on immediately without touching the steering.

I suspect the ARC module but can’t find a second hand unit with the same serial number. Mine is NNW504024 (oldest version). Has anyone got experience with changing the module and if so do you know which module would be compatible.

Thanks In advance

Have you tried the install new module procedure on the steering angle sensor?

Next look at live data from the accelerometers. 2011 RRS HSE Luxury 3.0 TDV6 Fuji White on Ebony/Ivory
Born and raised in So Cal. Moved to the UK in 2018 for a few years. Now in Poland and looking at moving back to the UK.

I’ve calibrated the steering sensors centrally and checked they don’t go past 580 degrees each way

Try the install new module procedure. I’ve had multiple calibrations fail and then done the install new module procedure (reinstalls the software) and it works fine. 2011 RRS HSE Luxury 3.0 TDV6 Fuji White on Ebony/Ivory
Born and raised in So Cal. Moved to the UK in 2018 for a few years. Now in Poland and looking at moving back to the UK.

There is no install new steering angle sensor feature on the GAP IITool, just a calibration feature. I have since tried to recalibrate the ARC module which failed and has caused a red fault light, C1A00-54 (AF) due to ARCM missing calibration.

The Guys at Gap-Diagnostics have said the ARC module is refusing commands and cant be calibrated until the Steering sensor Fault is sorted

I can calibrate the Steering angle sensor (only faults when engine running) and the live data is fine and shows the sensor working smoothly. There is continuity and no damage on the earth wire, power wire or communication/network wires to the ARC module.

The Alternator charging voltage is just over 15 volts, I have ordered a new alternator to rule it out.