[JHZR2]

Ive owned my HAH since new. Never had an issue with starting the car, but I have noted the 12v battery is always low. A fully charged battery, it in a charger, should read 12.6-12.7V with a meter. Mine will drop to low 12s in a few days, and high 11s in a week or more.

It isn’t the issue it would be in a normal car, because it doesn’t do anything but unlock doors. It doesn’t crank engines or really serve big loads.

Recently I put a meter on it, saw low voltage, and charged it. I was playing around with logging multimeters. What I observed was this:

The top picture was data logging the charger operation.. All those drop outs on the blue line are from something on the car. It was just parked, hood open, everything off. Whatever goes on, does so fairly often, and loads it enough to cause all those funny drops for a number of seconds each. No wonder the 12v battery depletes!

Im going to use the logging meters with no battery charger attached one day to see just what/how often something is happening...

Has anyone had an issue with parasitic loads? Any TSBs or whatnot on this? Any info?

 

[2Accordz]

If the car never has starting issues, those drops may be normal.
Things like keyless entry, radios,including clocks, ECUs are going to be draws, that's just the way it works.

For example, keyless entry sensors work(in most cars) whenever the door gets opened, or the key comes in range, that may be part of what you're seeing also.

What you're looking at is akin to wearing a heart monitor all day long and then looking at the data...you'd probably be astonished that the "pacemaker" part of your heart isn't that perfect, either.

 

[JHZR2]

If the car never has starting issues, those drops may be normal.
Things like keyless entry, radios,including clocks, ECUs are going to be draws, that's just the way it works.

For example, keyless entry sensors work(in most cars) whenever the door gets opened, or the key comes in range, that may be part of what you're seeing also.

What you're looking at is akin to wearing a heart monitor all day long and then looking at the data...you'd probably be astonished that the "pacemaker" part of your heart isn't that perfect, either.

It is true that seeing what I’m seeing might be surprising because it’s looking at long-term data.

What is not appropriate/acceptable is for a lead acid battery to bleed down to low states of charge in no time flat due to those loads. A fully charged lead acid battery sits around 12.6V. High 11s/low 12s is unacceptable from a life and longevity standpoint. It is abusive to lead acid batteries. Maybe the hybrid gets a pass because it doesn’t crank the engine... but still...

 

[greg1c]

You need to see the amp draw when this is happening. You need to put your meter inline to measure that. You need to make sure the current draw would not exceed your meters fuse limit.


Here is a good video showing how to test.

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