External motor power MTR pin not working on sparkfun auto phat

Robotics
1

I’m trying to build a robot car using the sparkfun auto phat. I want to use the external power header on the phat for the power and not usbc but it is not working. I am supplying 7.2v via 6 AA NiMH batteries but it is not working. The motors will not run. 7.2v is within the range specified on the board when connecting to MTR external power. I have connected gnd pin to my external power source gnd.

However the motors and pi will run when I use the auto phat’s usbc port, the same batteries work fine on a similar custom made robot car, the pins I have soldered to external power on the phat have clean connections and all work fine when tested in continuity mode with a multimeter.

2

No it was a bad connection on a terminal connector between the battery and MTR pin. Sorry. Can’t delete things immediately after posting either.

3

Do you mind sharing how you have it all wired up? My first guess would be that the PWM signal is being lost somehow via the MTR header, and not via USB, so it likely points to either a wiring/config issue or a defective board - either case, we’ll get ya squared away

EDIT Just saw your updated/recent post, great!