E38 PCM controlling aftermarket Spal brushless pwm fan

[Age08]

I have found a weird glitch in the E38 pcm, I am trying to control a 17" spal brushless PWM controlled fan the frequency and voltage are with in specs of what the e38 outputs. the spal fan work's in reverse to the factory PWN siemens fan controller, on that 89% fan speed in the program equal 10% of the spal fan and 10% in the program equaled 89% for the spal fan.

When I inverted the two tables something weird happen when I tested it, the spal fan would come on at first but once the car got over 70-80c the pcm stopped putting out a pwm signal and the fan shut off.
Im guess there some weird logic that doesn't like to the fan duty cycle go lower when engine temp increases.

[joecar]

Thanks for posting.