Need help installing a VIC 3 in a XM813

[scottr208]

I just finished restoring my 5 ton and wanted to install a VIC 3 system with 4 FFCS and Bose headsets. I installed the MCS behind the seat and powered it on and it immediately gave me a TEST FAIL indication. Even with none of the FFCS's hooked up, it immediately goes to TEST FAIL. When the FFCS's are hooked up, the crackle and cut out. It still reads TEST FAIL immediatley. I suspect it was in the power hookup. It came with a power cord that was supposed to plug into a radio tray, but I don't have the radio tray. I cut the end of the plug and it revealed a white wire, a blue wire, and shielding. I put the white wire to the positive side of the batteries that produce 24v and the unit powers up. Thats without ANYTHING going to the negative side. I read in the repair manual that the system contains two power supplies so I hooked the blue wire to positve with no results. I think all of the poblem lies in my power connection and that the system will be GREAT once I figure out what to do with the white wire, blue wire, and shielding(If anything).

 

[scottr208]

No one?

Come on, there's got to be a current or ex commo person out there who's a lot smarter than me (it doesn't take much).

 

[KsM715]

Ummm you dont know how it works so you just cut the end off and stuck it to the battery?

The only way I can help you is to start searching and googling "vic-3"

 

[aleigh]

I realize this thread is ancient, but, I also know that we all encourage people to search for answers...

On the VIC-3 MCS, the A pin is +24V and the B pin is GND but floated to the regulator. The shield is the chassis ground. You can verify this - the power shell to the chassis is 0 ohms but the B pin has no conductivity. The MCS is reverse polarity protected. Correct wiring is to take BLUE(A) to 24V and WHITE(B) + SHIELD to GND. But verify your particular cable has WHITE to A, because who knows how sober the guy who made the cable that day was.