PWM radiator fan controller

[parsonsj]

A postscript:



Yesterday, I transferred the tune from the old GMPP file to the new ZR1 OS tune file. I moved every single table, one by one, and did a complete audit of all the DTC codes and their behaviors. The end result was unexpected, in a good way.

I finally fired up the car, monitoring all the usual parameters, including fan desired/fan %/AC pressure.

With an identical tune (as near as I can tell) the car runs better. The idle is smoother, throttle response is better, TPS % at idle is better (27% to 19%), fuel trims are markedly improved, and O2 voltages are smoother.

There's no doubt the car runs better with the ZR1 OS than with the GMPP OS, with an identical tune. Oh, and the fans function perfectly. AC and ECT desired both work exactly as documented.

Anyway, after 4 weeks' delay, the project is back on track. I'll never use a GMPP crate controller or OS again. From now on, I'll make my own harness, and get my own controller.