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Inconsistent voltage drop on start
Utilizing PDM15. Checked all grounds and connections are good, battery has been charged and tested good. We were seeing an inconsistent voltage drop while monitoring battery voltage in the software. This would cause the pdm to power off and interupt startup sequence, sometimes i could get the car to start by holding the key down to start. Some times we saw a dip down to less than 1 volt while monitoring battery voltage in the pdm software. We were also using oscilloscope to do additional monitoring at the post of the pdm. The scope didn't see as big of a drop as the software was reading though (about 6v). Battery and grounds are all 0gauge wiring, and the car has a relatively simple setup. I also verified that we aren't tripping any of the set fuses to cause a shitdown. Anyone have any recommendations as to where we can go…
I can confirm my issue seemed to be related to be my cars stock keyed ignition cylinder that i was using. We switched over to using a toggle switch for 'key on' power and then a push button for starter. After switching to using that setup the issue was resolved.