CWA400 PWM Control, Link G4+

Trying to get one of these pumps up and running on a subaru project. Due to limited I/O on the g4+ and running quad avcs, the only available GP PWM Output was the PWM that was used for fuel pump control (Aux Output 6). Pump is wired, Pwm wire is ran to Aux6, pump does run. But Im not seeing any change in Duty Cycle. My PWM table was set to ECT vs RPM, but for testing changed it to TPS (TP Main) vs ECT for Key On, Engine Off troubleshooting. Frequency is set to 150Hz, and Constant for the GP PWM setup. Pump wakes when table is set to 85% (inverted duty from what i have read) but there is no audible change in pump speed between 85% and 20%.

What does the PWM signal look like? You might need a pull-up to 12V if your output can't drive both high and low. I found that pump worked reliably at 100 hz.

The Aux ouputs are pulled up to regulated 12V with 1.5Kohm. Are you sure your pump is the PWM controlled version? Some of the BMW ones are LIN bus.

Thanks for the input guys. I had this pump ordered through the local german parts shop and may have gotten the wrong pump. The part number I received is 11515A05704, the part number from the tecomotive site come out to 11518635090. But these pumps fit a lot of the same vehicles and years. (ex. 535iX 2014-2017) according to the bmw parts website I was on. Not sure if anyone can confirm if this is in fact the right or wrong pump.

Ive contacted tecomotive to see if they can provide any information.

Actually the more I look, I suspect they probably all have both LIN and PWM, in the BMW they use the LIN pin but if that loses coms it fails over to PWM.

Pin #2 is shown as signal Gnd in the generic documentation and LIN in the OEM documentation.

Having trouble getting pics to display, maybe 3rd time lucky...

Interesting. Well next step is to measure amp draw while changing my pwm and see if they follow. You can clearly hear the pumo in the car and come up to speed when keyed on. Id expect to hear the speed changing as well. Thanks for finding that information.