Problem with Victron 702 Battery monitor

[Quadrille in JB]

I have had a Victron 702 battery monitor on my boat for about 4 years with no problems. My setup is 2-350W Sunpower panels, 2-Victron 100/30 MPPT controllers and 8-105 ah AGM batteries. The system always gets the bank up to 100% sometime during the day. Last week when I looked at the 702 it showed ~ -6 ah after the batteries were fully charged and the controllers had gone into float. I let the bank settle down for about an hour with the controllers and panels disconnected and did a reset on the 702. All went back to 0 but the display still showed a discharge of ~ 0.47A. This continued through the week. Yesterday I disconnected all loads from the system right at the main bus bars directly after the batteries. The shunt and 702 were still connected and the display still read ~ -0.47A. The history windows for the MPPTs show that the bank reaches full voltage each day and never drops below the set float level.
I think the problem has to be with the 702. Has anyone had a similar problem or does anyone have any idea of the possible problem?

[alamoana]

Backlight current draw? You have several settings if I remember correctly

[Stu Jackson]

Originally Posted by alamoana

Backlight current draw? You have several settings if I remember correctly

plus stereo memory?

[HeywoodJ]

If you are absolutely sure there is no load (the two posters above have pointed to some parasites) and this is a change from past operation then I would guess a dirty connection at the shunt or on the PCB on the shunt is resulting in a very minor reading from the shunt to the BMV.

I'd first check/clean all connections and see if it persists. There is a setting in the 702 (#9 in the settings menu) to zero the feed from the shunt when there is zero load. However, if you are getting new noise I would keep a very careful eye on things after zeroing, it may drift around more over time and require re-zeroing. Eventually that leads to a new shunt or PCB.

[Quadrille in JB]

Thank you all for your prompt responses. After disconnecting everything from the shunt and positive buss bars, I Reset the current reading to zero using option nine. I’ll check it out again today and let you know the outcome. Thanks again