TAC 50.04 MRL UCA3 Fault

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TAC 50.04 MRL UCA3 Fault #21693 09/22/17 09:39 PM
Joined: Mar 2014 Posts: 13 NY/NJ Area M MikeF stranger
MikeF stranger M Joined: Mar 2014 Posts: 13 NY/NJ Area	Hey guys, stepped into this job as a favor. New 2013 Tac 50.04 MRL. Bldg and TKE says they had a electrical spike. Only board showing signs of a problem is the little UCA3 board. The Fault light is lite up. Looking at the board there doesn't seem to be much to it. the picko fuse is good. Ordered a new one as TKE was going to do, but I have this feeling that's not going to be the problem. All of my TAC 50.04 documents don't have the UCA3 board in them. Is anyone familiar with this board and its function? Is there something that would cause it to indicate "Fault"? Any advise is appreciated. Thanks Mike-

Re: TAC 50.04 MRL UCA3 Fault MikeF #21694 09/22/17 09:46 PM
Joined: Jan 2014 Posts: 736 R Rolly old hand
Rolly old hand R Joined: Jan 2014 Posts: 736	UCA3 monitors the UPS supply

Re: TAC 50.04 MRL UCA3 Fault Rolly #21696 09/22/17 09:48 PM
Joined: Mar 2014 Posts: 13 NY/NJ Area M MikeF stranger
MikeF stranger M Joined: Mar 2014 Posts: 13 NY/NJ Area	ok, ill double check that to make sure all my voltages are good. Thanks-

Re: TAC 50.04 MRL UCA3 Fault MikeF #21724 09/25/17 08:41 PM
Joined: Jun 2017 Posts: 4 Canada J Jm160 Mechanic
Jm160 Mechanic J Joined: Jun 2017 Posts: 4 Canada	If the battery is dead it will fault out the uca3 board. There is a parameter that sets the time the brake picks on rescue op. I believe it's b43 temporarily set to a zero and see if the car runs. If it does then the battery is probably no good.

Re: TAC 50.04 MRL UCA3 Fault Jm160 #21730 09/26/17 03:37 AM
Joined: Mar 2014 Posts: 215 S Silly enthusiast
Silly enthusiast S Joined: Mar 2014 Posts: 215	There is a board in the battery that also can go bad, right where the (9pin?) connector plugs in. Have had a few bad on construction and that is the replacement part that gets sent out.

Re: TAC 50.04 MRL UCA3 Fault Silly #21864 10/11/17 03:36 AM
Joined: Mar 2015 Posts: 80 W Whadafack journeyman
Whadafack journeyman W Joined: Mar 2015 Posts: 80	replace the batteries

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