• Volvo 440: Voltage Decreases as Engine Speed Rises

    Having resolved the issue, it's a fairly garden variety fault, but I thought I'd document it in that the symptoms are almost exactly the opposite of what we expect to see when there's a fault with the charging system.

    Essentially, as the engine speed rises, the voltage (measured across the battery, or from anywhere else in the car) drops - and not just a little.