Toyota Prius 12V Charging System Functional Test

super like!

 

Excellent video
Just have to get me two of those clamp ammeters now (each one costs more than a new battery).

 

You don't HAVE to have expensive equipment to get a reasonable idea of what is going on with the 12 V system.
A $20 digital voltmeter is usually good enough.
The trick is to know what to look for.

No time to watch the whole thing right now but did get to the part where he shows the Gen 4 battery and says it is NOT AGM. I wonder about that statement because it looks like the individual cells are NOT vented.......and a conventional lead-acid type should be.

 

So for those with HUGE amplifierss, 100 Amps total, (1200 watts) but half of that may be used to run the car so a reasonable maximum would be 50 Amps (600 watts) for your stereo. And always be in Ready.

 

I’ve written about this before. The video shows the six vent plugs on the top of the battery from 0:59 to 1:05.

That seller seems to have assumed, incorrectly, that the 2016 Prius was a continuation of the third-generation, rather than a new model with a new type of battery. The two batteries they offer have good reviews from owners of other vehicles (one buyer mentioned having a 2012 Prius), but for 2016 and later, they are too wide and have the wrong terminal arrangement. Compare their photos with mine in this thread, and note the locations of the positive and negative terminals, relative to the closest edge of the battery.

 

I thought it was interesting that, with the car OFF, he had his center Fluke meter with Hall-effect clamp showing a current into the battery of around 0.6 amp, and he repeated that without any comment as to whether it's realistic, or where on earth that current could have been coming from.

It would have been perfect moment to point out that those Hall clamps are never super-accurate at the low-current ends of their ranges. His looked like it might have been an i410, which has an upper range limit of 400 amps, but down in the neighborhood of half an amp it isn't doing much but making up numbers. In this case, with the car OFF, the current was undoubtedly out of the battery, at somewhere under a tenth of an amp, and the fact that it looked like a few tenths of an amp in the impossible other direction was just an artifact of the measurement.

Always good to know the limits of one's instruments....

-Chap

 

That’s an interesting version of the diagram. I didn’t notice any errors, but it’s a completely different presentation than the Toyota Electrical Wiring Diagram published for 2016. Mitchell’s site says they redraw the diagrams for every vehicle into a consistent format.

 

the stock battery is vented and you do need to check on the individual fluid levels. use a dime to unscrew the six vent caps. use a flashlight to either check at an angle that the water level inside is just touching the base of the cap tube. or that the top down view of the parallel plates inside is distorted into an “eyelid” like dual convex lens shape. because when the water level reaches onto and touches the base of the cap tube it wicks up and distorts the view of the plates. if the level is too low the plates look parallel. and hold your breath whilst peering in. it’s sulphuric acid you’re smelling..

 

One GIANT step backwards, in my opinion.

I firmly intend to NEVER have to check the water level in a battery....ever again.

AGMs are great. And they work fine in systems that weren't necessarily designed for them.

 

I doubt that the level will drop in normal use, unless there's a problem with the inverter (or the 12v battery).

 

Totally wrong.

Just simple evaporation and being in the engine compartment where it is HOT will cause some water loss.
And "normal" charging and discharging creates some loss due to electrolysis.

Unless maybe you intend to buy a new battery about every two years regardless.......you NEED to check the lever at least every 6 months or so. More often in the beginning to get a handle on "normal" loss.

 

Well mine's over 2 years old now and the electrolyte level has not moved, this is the first time I've checked it.
Anyone else on here, apart from Sam, had to top up their battery ?

I've been driving for 45 years now and can honestly say the only time I have had to top up a battery was with the old dynamo charging systems where the charging voltage could get up to 16v or on other later systems where there was a charging fault.
It's just about impossible to "gas" a battery now with the control modern systems have on the charging of the battery, otherwise we would all be dying of sulphuric acid vapour poisoning.

 

Cars where the batteries are cranking an ICE possibly will need topping up. I've not touched the "maintenance free" batteries on my last 2 cars, though. And they both lasted in excess of 4½ yrs. There's no mention that TOYOTA topped it up on my 2yr old PRIUS.