Would a Prolong Charger deal with this issue?...

Hybrid Battery Exchange · Nov 15, 2017

priusrecon said: ↑

Found Something curious!

With that one errant block, I've been tracking the voltages, and when I measure the module voltages and compare
them to the total block voltage, I find there is a discrepency. The total block voltage does not add up to the
two individual module voltages for that one block like they do for all the other blocked pairs. Under all
circumstances (car on/car off/car on with load applied); all the module voltages are matching each other all
within 0.1V of each other, however, even though the module voltages are matching, that one block voltage can be
off from the others by as much as the error I keep finding in my block monitoring app, and can be off by as much
as more than half a volt or so. So I start checking around that block and find I'm getting a voltage difference
across the big brass strap connecting the two modules of that block (see picture).

This voltage difference goes away with the car turned off or in accessory position, but comes back when I turn it
on and put it under load, like chocking the wheels and putting it in reverse. I get anywhere from .3V to more than
half a volt in the few simple tests I've put it through. It seems the more current I put through it, the greater
that voltage drop through the strap.

Can somebody tell me what's happening and how to deal with it? ....And can that be what is setting off my computer
DTC's?
Click to expand...

Check your battery sensing computer and harness plug, is there any corrosion? Thoroughly check the sensing harness, I've seen cases where it would corrode to the point of separating.

priusrecon · Dec 1, 2017

The harness is in great shape. Most likely it was corrosion on the buss bars. After a thorough cleaning, I then used cleaned terminal nuts off of the other donor battery as they still had that anti corrosion plating on them, and then torqued to the specified torque. Car is driving great now, real solid and steady SOC meter, lots of electraglide endurance. All my block voltages are in lockstep. It's been over 800 miles since the repair and still no triangle and no codes. Fingers crossed, I'm putting the trim panels back in tomorrow.

Hopefully this little experience will help someone else having a similar problem.

Would a Prolong Charger deal with this issue?...

Hybrid Battery Exchange Member

priusrecon Member

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Would a Prolong Charger deal with this issue?...

Hybrid Battery Exchange Member

priusrecon Member