Gauges ( most) and trim tabs stopped working after battery change out

edgeofred

Had a reputable mech change out both of my batteries. Prior to this, I am 100% sure that temp, tach, trim and oil pressure gauges were working  great, also trim tab contol.  Now only the fuel and voltage gauges still work. Mech has yet to find reason but claims battery change out had nothing to to with it just" a boat thing".  Mech mentioned the Mercruiser "smart control?" box could be the issue. Three years (2011 Rinker, 276BR) with no gauge or trim tab issue and the very 1st timeter used after battery install this issue arises. Any thoughts or advice. Thank you!!

212rowboat

Does it run?  Assuming, it does (because you know the tach is dead)

Guess what?  All of those items except the two you mentioned are pcm controlled except the trim control.. 

A battery change could cause a pcm issue, but doubtful... They're pretty tough... 

I gotta agree with him, but not leaving him blameless:  look carefully around the area of the batteries for a stray wire (or bundle of wires) with a battery post loop on them.  I wager he simply missed reconnecting them. 

edgeofred

thanks, he mentioned that also. But the trim tabs seemed to be a head scratcher for him. yes, it runs. if it matters when tuning th ekey th edead gauges jump up for less then a second.

212rowboat

Then they likely have power... Turn your lights on and see if they illuminate for certainty... We're back to the pcm, now... Or a slave bundle that was disconnected inadvertently. 

LaRea

"Smart control" ... he meant "SmartCraft" which is the data bus used by late-model Mercruiser engines.  

frodo13056

Sounds like a grounding issue - or lack of grounding would be a better term. Check the battery area and see if you notice any loose wiring - often times there will be a 12 or 14 gauge black wire with a lug on it that is directly connected to the battery negative terminal. My guess is that he may have missed putting a ground wire or two back in place. I do most of my own work on my 320 and have a bunch of pictures of the electrical connections, wiring harness connections, etc. just in case I forget how stuff gets reconnected. 

edgeofred

thanks everyone. the mech that installed the batteries said he could make trim tabs work with a direct DC connection but they will not work when connected to the control box. He said the gauges are getting power (they jump up when key is turned on for a nano second) but after start up go back to resting on pin.  Fuel and Voltage gauges still work along with all other DC equipment such as water pump, GPS, Radio and etc.... He said I need to call a Mercruiser dealer as my 8.2 requires a special device to check status and/or reset? Claims the test set he has for the 8.1 will not work.  Man, this frustrating all was perfect before batteries were changed out. I welcome your input, once solved and I am broke I will share the fix!

rebel666

I had the exact same problem on my 296 which occurred this spring after replacing my batteries.  I rechecked all the battery connections and see nothing wrong.  Did you ever find out what happened?

edgeofred

rebel1666, Replaced AGI box, gauge sending units, blue control cable and tach. Boat almost working as before mishap but still need sending unit for trim gauge ( trim works) and need to address why fresh water pump also went out after battery change out. It has been a nightmare but can now see the light!