If your iProg+ unit is showing "PORT Errors" or "External Power" faults during self-tests, the following hardware changes are standard solutions found on professional repair forums like OBDII365: Resistor Replacements:
Avoid powering the iProg+ directly from a laptop USB port. Use a powered USB hub (at least 2A) with backfeeding protection to provide consistent current. Verification & Testing iprog rework
Change the pull-up resistor on the mainboard (typically marked with a green dot) to 4k7 . If your iProg+ unit is showing "PORT Errors"
A "good" rework isn't just about cleaning the board; it’s about correcting the electrical engineering errors. Here are the primary focus areas: 1. Power Rail Stabilization Avoid powering the iProg+ directly from a laptop USB port