Former Dodge family, Prius won't start.

The Prius is not like a conventional car as I and others keep saying. An extremely weak 12v still makes lights light up and sounds, just maybe not the right ones.

When you get some rest, you need to type out a post that actually says what's happening. Summaries from someone who doesn't fully understand the situation is not helpful. The people on here that know how the Prius is supposed to behave should be the one trimming the information.

Normally it should be: You get in the car. Without doing anything the brake booster will start priming the brakes (via the 12v battery). You put your foot on the brake pedal and press down. Your brake lights will turn on. You depress the start button. You will immediately hear some clicking noises from the back in the order of (a) engage the high voltage battery via the current limiting resistor and the ground, (b) engage the non-current limited positive voltage path, (c) deactivate the current limited high voltage relay. It is a click-click-pause-click-pause-click sound coming from under the rear seats. Then all the lights on the dash will illuminate (as per federal regulations so you know if any have been tampered with to just never illuminate). After a few seconds most of the lights will go out. The main one that needs to stay on is the READY light. If you wait a few seconds (usually less than 7 seconds), you should feel the gas engine spin up and turn on. The energy screen will start showing the battery recharging. This is without ever shifting or moving. If you get to this point, the car is fully ready to go. Then if you try to shift into drive by depressing the brake and moving the lever you should see the gear selector icon show a difference. If it is in N, or won't change, then it could be a gear shifter problem. They have been known to eventually gum up with lots of use and you have a high mileage car. One of my coworkers with a Prius shifts it between D and B and N with almost every traffic stop completely missing the point of owning a Prius. But that shifter will die a horrible death much earlier than it should. If you get it into drive but the car just doesn't move, that's a whole different set of problems.

We need actual info. No more summaries.

 

Location of the 12v auxillary battery is in the back right corner, in my 2nd gen. open the hatch and it is there on the back right,have to remove carpeted panel cover to get access.

*****Put the battery charger on the 12V battery, //////

(careful to observe polarity, black to NEG, red to Pos), 2 Amp charge setting if you have it,
see if its drawing many amps (not every charger shows the amp draw),
leave for 30+ min, comeback and see if start procedure is more responsive.

***** I take it you have no idea what a voltmeter/ multimeter is - for measuring the battery voltage level. (youtube is your friend) *****

CODE READER:
You can get a code readers pretty cheap, often $20 or less even at walmart.

It plugs into the OBD II port under the steering wheel/feet area.

 

If you really want to be certain, I would take @2k1Toaster up on his offer. He works with batteries for a living and is experienced with testing Prius batteries. He has even designed a replacement kit of new cells that is less expensive than the Toyota OEM one.

 

If you are using a website, find one of his postings in this thread. Click "Start a conversation" under hos username. This starts a private message just between the two of you.

 

Glad u got it going, -- the 12v battery test is a 'load test' --- this is an 'SLA' battery, like a deep-cycle battery, not meant for high fast drain like a regular car starter battery with holes in the plates meant to deal with short, high-draw for the starter and having higher CCA ratings.

The load test applies resistance and watches the current draw, the battery voltage should regain itself mostly, if it doesn't recoup quick enough then a % rating is applied to how much voltage is recovered.

The 12v battery is not exactly in an easy access area like most cars under the hood. For this reason, many don't replace it until they have to, esp. when they inquire about an OEM replacement and esp. when they contact the stealership for a quote on an oem bat. and labor for the job.

A mazda miata battery can almost easily be used as a sub, it can physically fit in the hole but terminal sizes and polarity locations are not the same, some mods have to be made. Also, the miata battery is a starter battery type, not the SLA type. There are some good alternatives to OEM (which is an AGM chemistry). I have even used a small 20A sealed electric lawn mower battery with alligator clips to terminals, not ideal, but it did get me by until able to get a suitable replacement.

 

Google Solar BA5. I have one of these, it's an electronic load tester, it works fine.

Or for a rudimentary assesment, just hook up a digital multimeter and check voltage at under-hood jump-point, when the car's off and all the doors closed.

 

You must be careful on substituting a different battery. It needs to be vented to the outside so the charging gasses do not enter the passenger compartment.

 

I would go OEM, but others say Optima Yellow Tops are great .

Just make sure either has the vent connection as mentioned above.

 

Consider logging into your nearest Pep Boys (or similar big box automotive retailer) website, go to their battery section, fill in your car info, and see what it comes up with. It is not early days anymore; the Prius is ubiquitous enough that there are a fair number of third party replacements: the aforementioned Optima Yellow Top, also Exide and Bosch. The latter two make batteries that are arguably more appropriate, similar to the OEM Yuasa, physically near-identical.

I went with Yellow Top when I replaced, 2 years back as of last September, but next time around (if it happens) I'm likely going with a Canadian Tire "Motomaster" battery, which is apparently a rebadged Exide.

Some info from my notes:

OEM battery info (measurements taken directly):
Battery id: S46B24R GS YUASA
length: 9 3/8" (238 mm)
width: 4 7/8" (124 mm)
height: 8" (203 mm) (plus posts)
post dia's:
Pos: 13 mm (approx)
Neg: 10 mm (approx
Weight: 310
----
Optima Yellow Top:
Group Size: GR#51JIS: 46B24R
CCA: 450
CA: 575
Length: 9.272 in
Width: 5.024 in
Height: 8.885 in
web page:
----
Canada Tire battery:
MotoMaster Eliminator Ultra AGM
Product Number: #010-5122-6
Manufacturer's Product Number: ELU-S46B24R
(rebadged Exide battery)
----
Above Canadian Tire battery is rebadged:
Exide FP-AGM51JIS
----
Bosch Premium Performance Battery Group Size 51
Part # 51-440BAGM
----
ACDelco ACDB24R Advantage AGM Automotive BCI Group 51 Battery

 

Why are you considering the Motomaster next time around? price?

 

Several reasons. Someone with more brain cells than me has noted that comparing to the OEM Yuasa, the Optima Yellow Tops (which I currently have) are somewhat excessively high in Cold Cranking Amps, and that Amp Hours is compromised to compensate, and the latter is actually more important, in Prius application. Something about the Yellow Top having more/thinner plates to achieve the higher CCA, but the design is less durable?

The Motomaster (aka Exide) is closer to the OEM in this regard. It's traditionally shaped AGM, correct posts, vent, etecetera, slightly cheaper than Yellow Top, and a whole lot cheaper than OEM through dealership.

 

The Canadian Tire store branded items used to be well made.
Are the Prius that popular up there that they had a store brand battery made?

 

There are lots of second and third gen Prius cabs, they're predominant I'd say, and a moderate amount of privately owned Prius, about the same mix. Fourth gen are still quite rare, I'll see one maybe once a month? I have a habit when walking the dog, to sometimes do a poll of the cars rolling by, and somewhat sadly I'm seeing more and more SUV, CUV, truck, minivan, oh wait: a sedan. Then: more SUV, CUV, sigh...

Anyway, my one experience with a Canadian Tire went very well. For starters, they had a whiz-bang electronic load tester in the store, and were happy to check the battery before I took it. This was for our son's Civic, and when I had the old Honda battery and Motomaster side-by-side, you could see labels aside the two were more or less identical. Kind of like Costco "house brand" tires?