Yesterday my blower motor suddenly stopped working when I started the car in the morning and my climate control display started flashing (indicating a fault). I immediately suspected a faulty blower motor as it started making chirping and screeching noises intermittently since February this year.
The issue is, I'm not exactly sure if the fan control module is faulty as well or just the blower motor, I did a voltage test with digital volt meter at the two wires going into the blower motor coming from the module and got 12,4 volts at the power when ignition is on and 12,4 volts at the ground when the fan is turned on (but no ground when fan is off).
The problem is I can't tell by reading the repair manual if the voltage should be 12 V even at different speeds, it seems to me that all the module does is it acts like a variable resistor to control voltage output for the fan speed as well as a relay. When the ignition is on it sends power to the fan but there's no ground, then when you turn on the climate control it closes the ground to the fan so it starts to spin but it should show different voltages depending on the desired speed, when I see a constant voltage at ground and power regardless of input it makes me think that the resistor part of it is faulty since it can't limit the voltage (would make blower motor work at full speed).
(current flow diagram)
Reading the diagram J126 (fresh air control module) has five wires connected to it (6-slotted terminal), three from the climate control unit (E87/J255) which sends input from the driver and other stuff and then two wires going to ground (53 which leads to ground point 99 in another page) and power (Fuse 36). There's two wires directly going to the fan motor (power/ground) as well shown in the diagram without much detail.
Is the control module supposed to send constant voltage at different speeds to the blower motor or am I misunderstanding how a blower motor control module works? It seems unlikely that both the control module as well as the fan stopped working at the same time.
Car: 2004 Seat ibiza 6L
Mileage: 110000 km (63000 miles)