This software works only with a diagnostic cable . You cannot use Bluetooth alone. The cheapest verified cable is the EasyStart Web USB adapter (clone) or a homemade K-Line interface (using an ELM327 modified cable).

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Because of these high costs, a grey market solution has emerged: that runs on generic FTDI or K-Line adapters (like VAG KKL cables). This is where the "MHH Auto" community comes into play.

Unverified software can brick your heater’s ECU or infect your workshop laptop.