AMP EFI MS3Pro - Maintenance Inside the Case; Changing the Fuses

3.5 Maintenance inside the case 3 MS3PRO HARDWARE
• MicroSquirt transmission controller
• AMP EFI CAN-EGT thermocouple interface
• AIMSport MXL, Racepak IQ3S, Race Technology Dash2Pro, and other display dashes
• Third party CAN enabled wideband O
2
sensor controllers
3.5 Maintenance inside the case
The MS3Pro has several parts designed to be easy to repair in the unlikely event that the user needs to service
the ECU.
3.5.1 Changing the fuses
The MS3Pro uses two replaceable fuses. The F1 fuse protects the main input; if it blows, the entire MS3Pro will
shut down. The F2 fuse protects just the TPS reference voltage output. If it fails, you lose the reference voltage in
the wiring harness, but all internal operation in the MS3Pro will continue as normal. If you have a fuse blow, please
check to be sure there are no short circuits that may have caused the problem. (Note that a short circuit in VREF
can cause either fuse to blow.)
To remove the fuses, use a needle nose pliers to pull the fuse out of its holder and press a new fuse (available
from AMP EFI and its resellers) into its place.
AMP EFI MS3Pro manual version 1.202, firmware 1.5.0, 4/21/2017 Page 28