Mercedes M113 Project ; W205Cooling Fan Problem

[urr]

Hi,

I am working on a project involving a 1970 Mercedes SL280 with an M113 engine. We plan to use the radiator fan from a Mercedes W205 model. Additionally, we will be using the Link Extreme X ECU.

However, we encountered an issue: we intend to use the radiator fan for both cooling and air conditioning, but I am unable to control the fan via PWM from the ECU. The fan runs at full power at 22 Hz, but when I vary the frequency, the fan stops. Since we want to use the fan for both cooling and air conditioning, we need to vary the fan's power.

Our fan socket have 4 pin ; 

1. Ground

2. + V

3. ignition 

4. PWM signal 

Do you have any suggestions on how we can achieve this? A picture of the fan model is attached.

Thank you in advance for your help!

[dx4picco]

you could use a GP PWM output with engine temp on one axis and AC compressor on the other?

so not use the engine fan function in itself. 

fix the frequency at I guess something like 100Hz?

the duty needs to vary, not the frequency

[urr]

Thanks for the quick response. But I tried the procedure you mentioned, and I am unable to control the fan rev speed. I would like to make the fan rev speed variable. Because it works always full power.  I have tried many things but cannot figure out why this is happening. Do you think it could be due to the fan model and motor?
Thanks again!

fan.zip

[Laminar]

Change Frequency from Table to Constant. The Mercedes/GM/Ford fan controller that I use likes constant 100Hz frequency and varied PWM for speed. Not sure if yours is the exact same model.

https://rennlist.com/forums/928-forum/917865-mercedes-or-corvette-pwm-cooling-fan-controller-info.html