How to Read Battery Capacity with Autel AP200?

 Background

One of the most important, expensive, and worrisome components of any electric vehicle is the high-voltage battery that propels the vehicle. These batteries, although designed for long life, will deteriorate over time and affect vehicle range performance. All manufacturers are required to provide a warranty for the HV batteries. For the Clarity, this warranty is 8 years, 100K miles in most states. It increases to 10 years, 150K miles if your vehice is registered and normally operated in California, Connecticut, Delaware, Maine, Maryland, Massachusetts, New Jersey, New York, Oregon, Pennsylvania, Rhode Island, Vermont, and Washington.

In the case of the Clarity, the specifics of the HV battery warranty are based on a capacity measurement of the battery expressed in ampere-hours (Ah). This warranty is spelled out in the pre-delivery checklist (17-093) that is supposed to be provided to all new owners.

The nominal battery capacity for a new vehicle is 55 Ah, and Honda defines the eligibility for warranty replacement as being 2/3 of the nominal capacity, or 36.6 Ah.

It is not industry practice to make an electrified vehicle's battery capacity readily available to owners and Honda followed that practice. Instead, Honda intended this readout to be available only to dealer service personnel, believing they would be better able to interpret that value. Honda equips dealer service departments with a Honda-specific system called "i-HDS," which can extract the battery capacity value along with much other diagnostic information.

Unfortunately, some Honda dealers do not have extensive experience servicing the Honda Clarity Plug-In Hybrid and do not know about the battery capacity. In this case, presenting the service adviser with a copy of this PDI page will help them understand the Clarity PHEV's battery capacity and how to read it.

In addition, many dealers charge a fee to read the battery capacity (unless you happen to be there for other service anyway, and you are nice to them).

However, even if your dealer is willing to provide the battery capacity of your Clarity PHEV for free, it would be much more convenient if you could read this value yourself whenever you choose to do so, and this repository will provide several means to obtain this measurement yourself

Accessing the Battery Capacity Yourself

HV Battery Capacity is accessed through the OBDII connector which is located under the dashboard above your left leg. This is the same connector that allows access to the vehicle computer systems for diagnostic testing as well as emissions inspections. The OBDII connector contains provisions to access the vehicle’s Controller Area Network (CAN) bus.

This repository identifies 3 ways to read the HV Battery Capacity from the Honda Clarity PHEV

Option 1 - The Autel AP200, with MaxAP200 App (and pre-authorized V2.01.54 Beta version of Honda Diagnostics)
Option 2 - A Proven 'good' ELM327 OBDII adapter with the Car Scanner App
Option 3 - A Proven 'good' ELM327 OBDII adapter with a PC or Laptop, generating a formatted report

Autel AP200 is a great device to have. 

How to Read Battery Capacity with Autel AP200?

What do you need for this approach: 

1. Autel AP200 OBD2 Adapter (Cost around $60) 

IMPORTANT – There are newer variants of Autel OBDII adapters. For a variety of reasons, you want the original AP200. The variants that we do NOT recommend have a letter after the name – for instance, the AP200H, AP200C, AP200M.

2. Android phone (Must be a 64-bit version of Anrroid) 

3. Internet connectivity 

Necessary Firmware Authorization:

 The AP200 production diagnostic code does NOT support the Clarity Electric Powertrain functionality. In order to access the required Beta code (2.01.54) you must request access to the Beta code from Autel.

To do this, obtain your AP200 first (you will need it’s serial number), and send an email to Autel technical support. Here is a suggested template 

Send to- support@autel.com 

Subject - Honda Beta 2.01.54 

Access Message – Please authorize my AP200 (S/N CAP2xxxxxxxx) for use with the Honda 2.01.54 Beta diagnostics. 

Vincent Liu has been their support person who worked with us from the beginning. They are supporting InsideEVs forum members as a courtesy in lieu of officially releasing this function in their released versions. Please be patient as they are busy with all their other priorities.

Procedure to use:

From the Google Play Store, install the program called Autel MaxiAP200 on your phone. When you run the application, it will require you to log in to Autel. 

If you do not currently have an account, then use the “Register” function to create one (this is a free account, but you must have a login to us the AP200).

Once you are registered, then login to the account.

You will see a screen like this:

Select Diagnostics. 

The Autel AP200 scanner allows you unlimited free access to one vehicle manufacturer. You will want to add Honda as your free vehicle. Use the “+” and browse to Honda and add it. If your request for the Beta code has been processed, you will see v2.01.54 as the version to download. Select ‘Download’ to install it. If you see a different version, it is because your Beta request is not active. You can proceed and download / install the production version that is shown if you want. It will give you access to many functions, but not the Electric Powertrain needed for battery capacity. When the Beta code is authorized, it will be offered as an update. 

During the install, you will get a message that says: 

“Secondary App is needed for normal diagnosis. 

Please go to GooglePlay to download the APP:DiagAsia.” 

Select OK, then Install to obtain ‘Diag-Asia’ too. 

Now, back at the Diagnostics screen, you should be able to Download the Honda diagnostics. You will also see two other diagnostics entries (“Eobd”, and “Demo”). 

You can download and install those too, as they give you even more free generic functionality. 

When you are done, you should see something like this:

At this point, you are ready to connect the AP200 to the vehicle and obtain the Battery Capacity information from the Electric Powertrain. Connect the AP200 to the OBDII connector and “start” the vehicle (remember to depress the brake when starting) 

Now, you can select “Honda” on the diagnostics screen. It will tell you to connect the “VCI” (this is the AP200). It should see your AP200 and allow you to pair with it. 

Here is what the screen will look like when pairing is complete:

You will then see a screen allowing you to “Select Diagnostic Type”. Choose “System Selection”, then “USA”. It should report your vehicle information (including your VIN number). Select “YES” at the bottom of the screen. Select “Control Unit” and you will have a list of all the various vehicle subsystems. You want to select the “Electric Powertrain”. It takes a while to communicate with the vehicle, and once it is done, you can select “Live Data”. Now you should have a screen with a LOT of parameters shown. There is a lot to digest here, but at the bottom of the 1st sreen you will find the Battery Capacity. Here is an example:

The best thing to do now is to do a “Save”. It will create a comprehensive nicely formatted .pdf file with ALL of the Electric Powertrain data. If you then use the “PDF Preview” button, it will show this on the screen and you can sent it / email it to yourself.

Here is an example of the PDF preview:

Note: This is not intended to be a tutorial on how to fully utilize the Autel A200. It has a lot of capabilities that are more geared to the serious DIY user. You can explore all of the various features available on your own.

Which should I use ?

• If you are an avid do-it-yourselfer, you my want to consider Option 1 because the Autel device provides a LOT of diagnostic information about all of the vehicle systems (not just the Electric Powertrain which contains the Battery Capacity)

  • Requires special request to Autel to authorize 2.01.54 Beta version of Honda diagnostics
  • Autel is sometimes not as responsive as we would like

• If you are a beginner and not so technically inclined, then Option 2 is recommended, and is easy enough that almost anyone can be successful with it.

• Once you are configured for Option 2, then you can also try Option 3 if you would like nicely formatted reports

• Many have both the AP200 and ELM327 setups because really the costs are very low

Note - There is LOT of discussion on the InsideEVs pages for each approach (linked in the table above). These discussions were evolutionary and sometimes highly technical. This is part of the reason for this How-To guide. The original threads became far too cluttered for most to easily interpret. They contain a lot of information, but hopefully this simplified How-To will be all you need to get started. Feel free to post any comments and discussions in InsideEVs. There is a lot of help available there if you are having trouble.

Sharing of Battery Capacity Measurements

In the interest of learning more about HV battery behavior, InsideEVs forum members are cooperating and entering battery measurement data into a shared spreadsheet. This will help identify trends and you can easily see if your Clarity is out of character with others. You are encouraged to participate in this important effort, and you can get to the spreadsheet HERE

Odd 'Resets' of Battery Capacity

There have been some anomalies reported with the capacity readings

• We have seen a few examples where the battery capacity seems too good to be true. Remember that a factory new battery is 55 Ah. In these instances, it seems like the reading continues to report 55 Ah even as usage / mileage shoud reveal some degradation. Either these owners are 'babying' the battery in some unknown way, or the reading is 'stuck' for some reason and doesn't reflect the actual capacity.

• We have also seem some examples where the battery capacity seems to get "reset" back to the factory setting. In these cases, the capacity was slowly dropping as expected, and was at a 'reasonable' setting when suddenly it jumps up to 55 Ah. Something unknown causes this reset, after which it begins to return back to the 'normal' reading just before the reset. The process of returning to 'normal' seems to take very long (months?). We know that disconnecting the 12V battery for a brief period does not cause a battery capacity reset, but the speculation is that disconnecting the 12V battery for a 'prolonged' period might (maybe a day or more?).

FYI:

Based on a correspondence today with Autel...
I am now recommending that you purchase the original AP200 and NOT any of the newer ones (AP200C/H/M).

Reasons:

The bottom line is that Autel not only overly complicated a nice simple product, but they made a major change to their ongoing pricing that significantly impacts the desirability.

The bottom line is that ALL of the new devices require ongoing (Annual) subscription payments. This annual payment is not just required to obtain updates, but the device will cease to function (even at whatever the current revision is) if the annual payments are stopped.

The original device (for the single manufacturer chosen) does not have any ongoing fees and lifetime updates are free. If you choose to purchase a second manufacturer, then there is a $22 per year subscription fee that applies to each additional manufacturer. If you wanted 2 manufacturers, you [could] trade off the cost of purchasing two AP200's vs. the cost of purchasing one and paying $22/year for the second manufacturer.

In actuality, having to pay ~$20 per year for this kind of functionality is not a bad deal, it's just that the AP200 offers a much better deal (Free)!

Just to give you the words straight from the horses mouth, here is the correspondence from Autel Customer Support:

************** Autel Correspondence - My questions in black, their responses blue **************

For the original AP200:

• Free download for ONE manufacturer
• Free lifetime updates for that one manufacturer
• Additional manufacturers $21.99 each
• Is there an annual fee for updates to each additional manufacturer?

The firs free software is life time free, you can download any software as the first free software. If still need extra software, you can purchase the software one by one, and each software will cost 21.99 USD/year.

• Do you plan to discontinue this original AP200?

At present, there is no plan to discontinue the original AP200.

For the AP200C:

• Purchase includes all manufacturers
• Do you get free lifetime updates for all manufacturers, or is there an annual fee?

The AP200C software purchased by systems, and the ABS+SRS system combined as the first free system and only the first year is free. Then need to purchase annually.

• If you do not renew the subscription after 1st year, does the device stop working entirely, or will it continue at whatever revision existed prior to expiration?

If stop renew the subscription after 1st year, then the whole system can't be used.

For the AP200H and M:

• Free download for ONE manufacturer
• Are updates free for that manufacturer for only 1 year?

Yes, correct.

• After that, additional updates will cost $19.99 per year?

AP200H is 15.99 USD/year for each software;
AP200M is 19.99 USD/year for each software.

• If you do not renew the subscription after 1st year, does the device stop working entirely, or will it continue at whatever revision existed prior to expiration?

If stop renew the subscription after 1st year, then the corresponding software can't be used.

If you have a document that clearly explains how these fees work, please point me to a copy.
Really sorry that there is no document.