I'm in need of help understanding a relay schematic from an automotive relay that has broken on my Triumph. I can find replacement relays of the same model number, but I was curious as to why the relay is wired differently to most other relays I have come across.
It is a
Hella 4RA 940 010-71. It has a resistor in parallel with the coil, but then has a diode in series with the coil as well. See the below pictures.
I understand the use of the resistor, but the diode confuses me. If it is low side switched, then when switched off, surely a huge positive voltage spike will appear at the negative side of the coil, which the diode won't block, as it is forward biased.