[CNGBiFuel]

'Faulty diagnostic signal from blower fan power stage'

To be clear, in how it's written - which isn't too clear, however they've likely 30 odd chars. max in hthe display.... the diagnostics will be referring to the power-stage of the circuit, ie: as distinct for the 'control-stage' (low current). What will be referred to as the 'power-stage' is the high current section of a circuit. Indicating our fault is in the power-stage of the circuit.

There is no one entity we would name 'A Power-stage', for want of a better parrallel, you might say an ICE has a induction stage, an ignition stage, a combustion-stage, an exhuast stage, and a transmission stage.

In this case, we have a resistor that sits in the power-stage of the circuit, and as the diagnostic states, it's causing a faulty diagnostic signal. Ask your electronics engineer for a power-stage, and he'll ask for a power-stage of what?

With a heat-sink, such that motors won't overheat and cook it, this component is a high-power resistor. I've been wrong before, however I doubt LHD or RHD has much bearing on which resistor Volvo specify in the heater circuit.