Hi Guys I need some help with my MS3x diy kit.
So I followed the turbokitty completed the MS3x kit for my 99 miata.
using a 12v battery to pin28 and pin19 on dp37 to power up the MS3x and try to load the firmware. But my computer will connected to the MS3x the first 10s then I will lost the connection. So I used a voltmeter to check the 40pin connector pin 32 to 20, 19 to 20, 2 to 20, I got 5v when I first turn on , but it drop to 2.5v after 10s! How can I fix this issue?

so someone please help me here! Thank you

 

Measure voltage on F1 and F2. These are thermal fuses, if one trips than at least you know something is pulling too much current. Check those circuits.

 

Good Morning, I checked the F1 and F2 this morning. I got F1 top pin stay on 5v , but when I checked the bottom bin and f2, the voltage will drop 5v to 2v.
I also checked U5, I got left pin stay on 10v, right pin stay on 5v. what should I check next?
Thank you so much for helping me

 

Are you saying that F1 has 5V on both sides, but F2 drops to 2V?
F2 feeds your TPS sensor. Something might be wrong with it (or its wiring).

 

Thank you again, I found the issue now, I got U7 in backwards!