Prius plug-in driver looking at Clarity as next PHEV - 2018 Honda Clarity Forum
 8Likes
Reply
 
Thread Tools
post #1 of 18 (permalink) Old 11-23-2020, 11:03 AM Thread Starter
Junior Member
 
Join Date: Nov 2020
Location: Massachusetts
Posts: 11
Talking Prius plug-in driver looking at Clarity as next PHEV

Hi everyone,
I currently own a 2012 Toyota Prius Plug-in Advanced.
It was recently in an accident and am looking to replace the car.

Any suggestions on finding 2018 Clarity Touring models?
I pinged BethInMyrtleBeach about her 2018 Clarity, but in case she sold it I'm looking for other leads.

Any recalls or other trouble spots I should inquire about when discussing any that I find?

I just got here but I seems like this is a very friendly place for Clarity owners to get together!

Thanks in advance for any answers to my questions above.

Scott
fufu is offline  
post #2 of 18 (permalink) Old 11-23-2020, 01:21 PM
Senior Member
 
obermd's Avatar
 
Join Date: May 2019
Location: Denver
Posts: 341
First question - where are you located? If you're outside California I'd check with your local Honda dealerships to see if they will support the car.

2018 Honda Clarity Touring PHEV - Forest Green w/Tan interior (wife's car)
2017 Volt LT - Heather Gray; black bow ties, Charcoal VoltShelf
2012 Cruze ECO MT (hail totaled 5/8/17 103,600 miles @42.5 MPG)
2010 Mit Lancer GT MT (traded for ECO @31K miles)
2002 Pont Montana AWD - title to son at college graduation
1990 Pont Transport (traded for Montana @240K miles)
1986 Fiero GT MT (traded for Transport - needed more seats)
1985 Fiero 2M4 MT (traded for Fiero GT @8K miles)
obermd is offline  
post #3 of 18 (permalink) Old 11-23-2020, 01:41 PM
Senior Member
 
Join Date: May 2019
Location: Atlanta, GA
Posts: 445
I would say the most important thing when buying a used Clarity is to have the battery capacity checked which can be done by any Honda dealer, and make this a condition of the sale. This is sometimes referred to as a capacity test but that's something of a misnomer because it's not as if they actually do a charge test, it's just a value stored in the vehicle's computer and the dealer just uses their diagnostic computer to read the value. Since most dealers have little experience with Clarity they often think you want the 12V battery tested, and even if you explain that you want the HV battery checked they don't always know how to do it, so you just tell them on their diagnostic computer go to the Electric Powertrain Data List and look at the Battery Pack Capacity. A new battery will be around 55 Ah, anything below that indicates that the battery has lost capacity, for example a value of 50 means that the battery has lost 10% of its original range. For a two year old Clarity that is not all that uncommon based on a lot of variables, but if the capacity is already diminished then that should be factored into the selling price.

The dealer may charge for doing this, which really the seller should be paying for but if they refuse and you otherwise like the car and plan to buy it then it's worth paying for the test yourself, just make sure you have it tested prior to purchase. If you don't have this checked, the odds are that it won't be a big problem, but if after purchase you realize that the battery has lost capacity there is nothing that Honda will do about it, it's not a warranty issue unless it drops below 36.6 Ah (33% loss) which so far no one has experienced.
fufu likes this.
2002 is online now  
post #4 of 18 (permalink) Old 11-23-2020, 01:48 PM
Senior Member
 
Join Date: May 2019
Location: Atlanta, GA
Posts: 445
Quote:
Originally Posted by obermd View Post
First question - where are you located? If you're outside California I'd check with your local Honda dealerships to see if they will support the car.
Any Honda dealer will support the Clarity. And even if it's the first one they have seen, Clarity has the same i-MMD hybrid system as the Accord and CR-V hybrids. Worst case if the technician can't figure something out using the troubleshooting instructions supplied by Honda, they will call Honda technical support, which is a normal situation whenever any new vehicle shows up in the service department, hybrid or not.

Now of course different dealers will have different levels of general proficiency (and customer service) but that will not be related to whether or not they are in California or whether they have experience with Clarity.
ClarityDave and fufu like this.
2002 is online now  
post #5 of 18 (permalink) Old 11-24-2020, 04:01 PM Thread Starter
Junior Member
 
Join Date: Nov 2020
Location: Massachusetts
Posts: 11
Thanks obermd. I am in Massachusetts. There are several new and used (2018) Claritys for sale around the state.
fufu is offline  
post #6 of 18 (permalink) Old 11-24-2020, 04:19 PM Thread Starter
Junior Member
 
Join Date: Nov 2020
Location: Massachusetts
Posts: 11
Thanks 2002,
I will add the traction pack capacity to my list of questions during inspection by the inspecting dealer.

I always take my prospective used car purchase to a dealer for that car's maker (not the one selling me the car of course &#128513 for inspection for evidence of collisions, mechanical wear, and any other problems.
I'll be sure to ask "Please provide a printout of the diagnostic computer results including the Electric Powertrain Data List" and pay particular attention to the reported Battery Pack Capacity.
Do you know if the report takes into account ambient temperature? I assume it does, given it's a parameter in good battery management systems.
fufu is offline  
post #7 of 18 (permalink) Old 11-25-2020, 12:03 AM
Senior Member
 
Join Date: May 2019
Location: Atlanta, GA
Posts: 445
The entire report is long and filled with data that you really can't do anything with, the only number you need is from the line for battery pack capacity. If they give you more than that you will probably find it interesting (even if not useful) I'm just letting you know you aren't missing anything if they just give you the page with the battery pack capacity.

Correction, I just remembered that someone said there is a value for longest time that the HV battery went without charging. If true this would be very useful as we know that some Clarities spent 6 months to a year sitting on dealer lots, and if the dealer was careless about keeping it charged then the HV battery may have run down to lower than it should, which would not be good. Unfortunately the value itself wouldn't tell the whole story, let's say it reports that 4 months was the longest period without charging. Well if the HV battery was full at the beginning of that period it should be fine. But if it was at 0 EV miles (10%) for example then after four months it could have discharged below what would be safe for the battery. The lowest it will go in operational mode is 1% and that is rare. If it discharged below that it likely is not good for the battery. But again no way to know what the battery level was during the longest period without charging. But at least if it says it never went more than say a month without charging then either A. it was not on the lot very long or B. the dealer kept it charged. To be clear I don't know for a fact that this information is available in diagnostics, just that someone said it is. Supposedly it also will tell you the same thing about the 12V battery, although that's not as big a concern, worst case they neglected the 12V and shortened its life, but the Clarity uses a standard 12V battery so low cost DIY replacement is possible, and some people have even gotten the dealer to replace it under warranty.

We really don't know how the HV battery capacity value is calculated, my theory is that it updates the value whenever you have charged to 100% SOC followed by a full discharge to whatever the voltage is that corresponds to 0 EV miles (10% SOC), with no charging in between (other than regen which it can account for). It then would calculate the Ah capacity based on how many kWh were discharged. That's my guess anyway. You would think it takes temperature into consideration.

Since it's a royal hassle to obtain the capacity most people have only gotten it once (if at all) and so we don't know if the number changes every time you charge, or maybe it averages the last few charges, or maybe it only updates if say the last three charges have been lower than the previously stored value.
obermd and fufu like this.
2002 is online now  
post #8 of 18 (permalink) Old 12-30-2020, 03:47 PM Thread Starter
Junior Member
 
Join Date: Nov 2020
Location: Massachusetts
Posts: 11
Hey everyone,
We've got a well negotiated deal on the table for this car, awaiting the 1-hour deep inspection by Kelly Honda (local to the Chevy dealer selling the car) tomorrow morning before we buy the car.

https://www.pridemotorgroup.com/inve...c5f31jc003341/
Carfax: https://www.carfax.com/VehicleHistor...ZC5F31JC003341

If anyone spots any red flags about this vehicle, please let me know!

I'll give an update with how the request for Battery Pack Capacity and time the traction pack went without charging" from the diagnostic computer output.
Is that interval without charging only including instances when the battery reached 100% SOC? I hope the battery is sized to allow charging to 80% of design so it will last longer.
Going to 100% SOC on Li-Ion cells wears them out faster, sweet spot appears to be 80% of rated capacity as I understand it.
fufu is offline  
post #9 of 18 (permalink) Old 12-30-2020, 05:13 PM
Senior Member
 
obermd's Avatar
 
Join Date: May 2019
Location: Denver
Posts: 341
I didn't see anything out of the ordinary in either. I would ask if the aftermarket service contract is still valid - you may have to ask the vendor directly - as it may save you money down the road. At that mileage I'd also ask for the number of miles on the engine. If they can't get that then ask for the overall MPG - higher means fewer ICE miles. There's a lot of miles on that car and it would be useful to know if they're electric or gas as this will give you some idea of how the car was driven. What you're looking for is the wear and tear on the injectors and spark plugs.

Also, this car should still have Garmin updates available. I believe the free five years transfers to a new owner.
fufu likes this.

2018 Honda Clarity Touring PHEV - Forest Green w/Tan interior (wife's car)
2017 Volt LT - Heather Gray; black bow ties, Charcoal VoltShelf
2012 Cruze ECO MT (hail totaled 5/8/17 103,600 miles @42.5 MPG)
2010 Mit Lancer GT MT (traded for ECO @31K miles)
2002 Pont Montana AWD - title to son at college graduation
1990 Pont Transport (traded for Montana @240K miles)
1986 Fiero GT MT (traded for Transport - needed more seats)
1985 Fiero 2M4 MT (traded for Fiero GT @8K miles)
obermd is offline  
post #10 of 18 (permalink) Old 12-30-2020, 07:31 PM
Senior Member
 
Join Date: May 2019
Location: Atlanta, GA
Posts: 445
Quote:
Originally Posted by fufu View Post
I hope the battery is sized to allow charging to 80% of design so it will last longer.
Going to 100% SOC on Li-Ion cells wears them out faster, sweet spot appears to be 80% of rated capacity as I understand it.
The battery is 17 kWh but people who have measured how much electricity is required to charge from empty to full say it's around 14.5 kWh. With charging losses the battery is probably only being charged just under 14 kWh.

Now on the surface that might sound like it's only using 80% of capacity (14/17=0.82, HOWEVER, 0 EV miles on the Clarity is 10% SOC, when it drops to that level the gas engine runs as needed to keep SOC between about 7-12%. But if you do things like sit in the car in the parking lot with the heater or AC running, or sit in stop and go traffic, SOC can get down as low as 1% before the engine comes on, then it charges it to about 3% then shuts off until it drops to around 1% again. So this means the actual usable part of the battery is between 1% and 100%. If the people who did the measuring were charging from 0 EV miles (10%-100%) that means the 14.5 kWh of charging that they measured represents only 90% of the actual useable charge. If they had drained the battery down to 1% before starting their charge test then they would have probably recorded about 16 kWh of charging (14.5 / 0.9 = 16.1). Charge losses might bring that down to say 15.5 kWh, which would be 91% of the 17 kWh. Not terrible but that's kind of getting up there.

For that reason I normally only charge my Clarity to 85% SOC which I figure is pretty close to 80% of the 17 kWh, and most days that amount of charge is more than I need. It requires using scheduled charging which for me I am already doing because I am on a Time of Use rate plan. Once you know from experience how many SOC % you get per hour of charging it's pretty easy to schedule a charge session that will get you pretty close to the SOC % that you want. Now on days that I know that I will be using the full EV range then I charge to 100%, but in those cases I schedule it to reach 100% shortly before my estimated departure, so that the battery will only be sitting briefly at 100%, which I have read is better for the battery than sitting around for hours at 100%. But we really have no proof of this, and many people get home and immediately start charging to full, which means their car sits at home for hours at 100%. And that may be perfectly fine, and I realize that's the easiest way to charge. But for me since it's just as easy to keep it well below 100% unless I need it. Now to throw a wrench in this the Honda manual says to always charge to 100%. One person theorized that maybe it only does cell balancing when you charge to 100%, but that's just a theory. But I charge to 100% at least once a week so I think I'm covered either way.
mowcowbell and fufu like this.
2002 is online now  
Reply

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Related Threads
Thread Thread Starter Forum Replies Last Post
Does the 18-097 apply to 2019 PHEV Clarity models? Having huge problems charging. Duxa Honda Clarity Complaints, Issues And Problems 9 01-11-2020 11:55 AM
Just got an '18 Clarity this week! Excited and learning! nhdabzr New Member Introductions 10 11-30-2019 01:39 PM
Honda's Commitment to Clarity PHEV JimWoo Honda Clarity Plug-In Hybrid 6 10-28-2019 06:30 PM
2018 Clarity Touring vs. 2017 Volt LT obermd 2018+ Honda Clarity Versus the Competition 0 05-19-2019 08:36 PM
2018 Honda Clarity Overview Administrator 2018+ Honda Clarity News 0 05-30-2018 08:20 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome