Taken from a different thread, sorry I was thinking about the Climate control version which is what my old car had, they didnt have resistor packs, so I wasn't lying to you, just got confused with a different model.....



All the speed control is on the ground side of the blower motor, the ground connection goes to the switch.



its known for the switch itself to fail so no ground is available to the resistor pack (1-3) or the motor direct (4).

The only different heater/resistor I know of is for the digital EATC version. No resistor and electronic control of blower speed.