Bench tests?

Is there a procedure to bench test the HIC and/or Power modules with a multimeter?

912iS Sport installed in Van's RV-12iS, wiring harnesses built by Stein Air Inc. via Van's Aircraft, limited personal electrical experience:

I am having multiple avionics anomalies with a new RV-12iS build (engine not running yet) upon first G3X/IFR startup.  When the Master power switch is turned on:

G3X displays "ENGINE ECU" and "ECS fail" yellow warnings on boot up.

Shortly thereafter, the top red LED on the back of the Power module and the Green LED on the GEA 24 begin flashing.

A white LED lights up on the HIC module

The LEDs on the fuel pump(s) and Lane switches stay on regardless of the switch on/off status.

The fuel pumps do not work, however they did earlier in the build.

The Rotax fusebox lights up, however, starts to slowly dim when either Lane switches are turned on.  With both Lane switches turned on the LEDs in the fusebox fade to dark.  The voltage at the fusebox X3 connector reads: 9.4V at terminals #1 & 2 = 9.4V and 13.4V at #3 with the master on and Lane switched off.  When the Lane switches are on, the voltage at terminals 1 & 2 drops to 4.7V.  #3 remains steady at 13.4V.

My partner recently recalled the 30amp EMS fuse on the panel blew the first time we switched the EMS Backup Battery switch on.  At teh time, there was a battery charger (designed for 12V aircraft batteries) attached and set to constant voltage. The fuse was replaced and has not tripped since.

Discussions with Van's Support have yet to solve any of the issues.  Discussions have included the possibility of a defective/malfunctioning HIC module. Wiring continuity (per data I have been able to find) and connections have been rechecked along with confirming the correct numbered wires to the correct terminals.  I am focusing on the HIC and Power modules right now and possible the EMS B/U battery switch

ANY SUGGESTIONS WELCOMED !!!