I have a power supply issue on my starter kit TRK-MPC5634M
Datasheet : http://www.farnell.com/datasheets/1637030.pdf
When I want to supply the board externally ( 9V-12V barrel connector ), the D4 LED turns RED ( safe mode ). When I supply the board by USB all is fine.
This LED D4 is connected to MCZ33905 ( Datasheet : http://datasheet.octopart.com/MCZ33905S5EK/R2-Freescale-Semiconductor-datasheet-8821163.pdf )
Informations about this "safe" is :
"Output of the safe circuitry. The pin is asserted LOW in case of a safe condition is detected (e.g.: software watchdog is not triggered, VDD low, issue on reset pin etc.). Open drain structure."
I checked th device VBAT, which is correct. For other condition I don't know how to check if there is an issue on reset pin or watchdog.