Factory Service Manual?

Discussion in 'Clarity' started by pinrut, Jul 24, 2018.

  1. pinrut

    pinrut New Member

    Is there somewhere I can purchase a (preferably) digital version of the factory service manual for the PHEV Clarity?

    I do most of my own service and the service manual would be very helpful,

    Thanks in advance!

    Edit: found the subscription based website with the repair information:
    Last edited: Jul 24, 2018
  2. jdonalds

    jdonalds Well-Known Member

    Free downloads available. I'm on the lake at the moment. I'm sure someone will point out where to get it.
    Carguro and pinrut like this.
  3. Atkinson

    Atkinson Active Member

    I wish I knew where the free service info was.
    I did $10 for one day access (all you can download).
    If there is a place for us to share, I can upload everything I have for our community, a little over 100 files and about a Gig in size.
    I grabbed easy stuff for general Clarity maintenance: brakes, engine and transmission oil, coolant, plus anything I was curious about.
    There are also tons of diags, schematics, and troubleshooting docs that are targeted for a deep dive so you really need to have specific issue before justifying the time to search and download the obscure stuff.
    KentuckyKen and pinrut like this.
  4. KentuckyKen

    KentuckyKen Well-Known Member

    I would really like to have a copy of what you downloaded and would be willing to help pay for some of your subscription. I’m not very computer savvy and lost my teenage tech support years ago when he fledged and left the nest. Could I snail mail you a thumb drive or is there a better way?

    Also, I found this while searching for a service manual before I found out that Honda quit selling them (I hate this subscription thing).
    I have no idea if this includes our Clarity or even if it’s legit or not but it purports to be $6.95 for 30 days. I assume they are reselling access to their paid subscription but don’t know if this is legal, ethical, or legit. ???

  5. Atkinson

    Atkinson Active Member

    Never heard of this, but with 96.5% positive feedback, you will probably lose your money.
  6. pinrut

    pinrut New Member

    Yeah, the eBay seller has over 300 ratings with a 95% overall rating, it might be legit after all
  7. Carguro

    Carguro New Member

    Set up a Google drive and if you can post the link here, do you recall downloading anything about the transmission?

  8. Heino

    Heino Active Member

    I’d be interested in this as well...
  9. KentuckyKen

    KentuckyKen Well-Known Member

    Is there some way we can coordinate this with each of us paying a daily fee and downloading a different section and then sharing. Or is that prohibited by Honda or too hard to do? If neither, I’d be willing to pay for downloading a section.
  10. The Gadgeteer

    The Gadgeteer Active Member

    The service manual may yield answers to the many Clarity PHEV mysteries.

    Looks like there is also monthly and yearly subscription pricing.
  11. insightman

    insightman Well-Known Member

    The online service information will reveal only the mysteries of how to take the Clarity apart and fix it--not all the mysteries of why it does what it does. For example (the example I always use), why it starts the ICE in response to regen braking when the battery is fully charged. In contrast, the non-plug-in Honda hybrids use up the regen power that cannot go to the fully charged battery by powering the starter motor/generator to spin the ICE without allowing the ICE to start. (Sorry, I know I spend too much forum space pondering this one question.)
  12. leop

    leop Member

    I think (warning: an opinion and not a fact) that the Clarity PHEV starts the ICE when the ICE is needed to absorb the regen energy so as to make sure that the ICE warms up. The Honda hybrids that I have driven have the ICE running all the time except when the vehicle is stationary. The engine is warm (or will be warm soon) and the oil is nicely circulated. Thus, the hybrid's ICE can be spun over (fuel and spark off) without the need to warm the ICE up. Yes, the PHEV ICE can be spun over with fuel and spark off without making any water that needs a warm engine to evaporate away (like any air pump). However, given the varying operating conditions (temperatures), a PHEV needs to warm up the ICE to make sure that the oil is circulating correctly and at a reasonable temperature. Finally, any cold ICE startup, when the oil is cold, is a time of great wear so why warm up the ICE matter when no water is made. The cylinder walls heat up fairly fast when the ICE is running (with spark and fuel) and the circulating oil gets rid of any wear particles produced. I think it is better in the long term to warm the ICE up after every cold start.

    Just my thoughts for what they are worth, LeoP
  13. MrFixit

    MrFixit Well-Known Member

    I looked at the Terms and Conditions on the 'techinfo.honda.com' site.
    Not surprisingly, Honda is pretty clear about this sort of thing...
    Here is the relevant section:

    Intellectual Property
    You acknowledge and agree that information, and services available on the Site are protected by copyrights, trademarks, service marks, patents, trade secrets, or other proprietary rights and laws and are owned or licensed by Honda. Except as expressly authorized by Honda, either in these Terms or elsewhere, you agree not to sell, license, rent, modify, distribute, copy, reproduce, transmit, publicly display, publicly perform, publish, adapt, edit, or create derivative works from the Site, information, or services. Without waiving any of the foregoing rights, you may print or download information or products from the Site for your own use, provided that you keep intact all copyright and other proprietary notices. Systematic retrieval of information or services from the Site to create or compile, directly or indirectly, a collection, compilation, database, or directory without written permission from Honda is prohibited.

    The complete T&C is here if you want to do any additional 'lawyering':

    I'm sure sharing a few common service manual downloads on an informal ad-hoc basis would not cause any harm, but I fear that a concerted effort to gather and freely distribute the whole manual or large sections would be unwise.
    KentuckyKen likes this.
  14. MPower

    MPower Well-Known Member

    What a concept! How about the Clarity Players dramatic performance of the service manual. (The heating system scene might be just a little too steamy.) Perhaps a choral reading would be more genteel.

    After the show we could all go out and watch paint dry or grass grow or really push out the boat by watching paint drying on growing grass--livin' large!
    The Gadgeteer, TomL and KentuckyKen like this.
  15. insightman

    insightman Well-Known Member

    How can the running ICE absorb the regen energy?

    Here is what I know:
    1. All Honda i-MMD hybrids use the engine to turn the starter motor/generator to generate power
    2. Honda's non-plug-in i-MMD hybrids use the starter motor/generator to turn a deadened ICE to use up excess regen power
    3. The Clarity Plug-In Hybrid is an i-MMD hybrid

    Clearly, using the ICE in its normal manner to generate additional power can't use up excess regen power.
    That means that the Clarity PHEV is using the ICE in a different way to use up excess regen power.

    Why would the Clarity require a different method of using up excess regen power? What makes the Clarity different from its non-plug-in siblings? The non-plug-in hybrids are the same as the Clarity, except for the size of their batteries. They, too, can travel under EV power, but just not as far. The bigger battery in the Clarity PHEV makes it heavier.

    The greater momentum of the heavier Clarity PHEV produces more regen power to be dissipated. Honda had to find a way to use the same i-MMD system to dissipate more power than the deadened-ICE scheme that works for the non-plug-in hybrids.

    My theory is that to use up the greater amount of regen energy produced by the heavier PHEV, the Clarity's starter motor/generator is actually opposing the running ICE by trying to slow it down. I don't like the idea that the Clarity is burning gas to get rid of electrical power it cannot store, but I'm not imaginative enough to come up with any other explanation. Below is the part of my unverified Clarity mode chart that illustrates this scheme.

    Last edited: Dec 31, 2019
  16. leop

    leop Member

    The Clarity needs to absorb energy from the regen system when the battery is too charged to do so. That energy can be directed to the generator/starter motor. However, the energy that goes to the generator/starter motor still needs to be absorbed. If the generator/motor is acting against a running, power producing ICE, the energy from both the regen system and the running ICE still needs to be absorbed. Where is the energy absorbed? It will not go into the ICE/transmission/starter/generator cooling system unless there is a practical way to generate thermal energy. I do not think there is such a way in the Clarity. Thus, trying to run the starter/generator against a running ICE (trying to slow down the ICE) is not going to absorb energy without violating energy conservation.

    On the other hand, turning over (spinning) the ICE will absorb energy and this can be so even if the ICE is running. On a non-hybrid car, taking ones foot off the accelerator slows the car down by engine braking even though the ICE is running. That is because the ICE, off throttle or with the fuel/spark cut off, is just an air pump and takes energy to spin. The Clarity ICE can be spun by the generator/starter motor to absorb energy. The ICE can have the fuel/spark off or can even be running at idle. The ICE, at idle, will absorb energy when it is spun faster than the idle rpm. I suspect that the Clarity ICE has the fuel/spark off when being spun to absorb the regen energy, just like on Honda hybrid cars, and only turns on the fuel/spark afterward to warm up the ICE. That is, I think Honda has decided that the Clarity ICE should be warmed up whenever the ICE is spun up.

    My earlier post was not clear that in that I was speaking mainly about the need to warm up an ICE after it is spun up to an operating rpm.

    BTW, there are many operating environments in which an ICE can absorb energy. The Jake brake on diesel engines works by making the ICE act like an air compressor (using more energy than just an air pump) by opening the exhaust valves at the top of the compression stroke. Also, even without a Jake brake, a diesel engine is a great air pump since there is no throttle (the intake is always wide open). We might be able to determine what the Clarity is doing when the ICE runs for regen when the battery is fully charged. An recording scanner on the OBD II port can record the throttle opening, the fuel flow, ICE rpm, and car speed (among other parameters). This will give clues to what is taking place. Remember that the Clarity has friction brakes (but not quite as large as one would expect in a car of that weight). So, regen braking is not needed that much unless the brakes are severely stressed or too hot.

    I have yet to have our Clarity start the ICE when braking with a fully charged battery. We do not have any downhill braking situations when near our house and we are careful braking for the first mile or so after charging the battery.

  17. Ray B

    Ray B Active Member

  18. insightman

    insightman Well-Known Member

    So you're saying that instead of trying to slow down the ICE, the starter motor/generator is trying to speed up the ICE? It seems like the energy-absorption problem you have with my slowing-down scenario would be the same with the speeding-up scenario. Why would trying to speed up the running the ICE have an advantage over not running the ICE, as the Insight and Accord Hybrid do?
    Last edited: Jan 1, 2020
  19. leop

    leop Member

    I have not been clear again. The Clarity is spinning the ICE just like the Honda hybrids and the Clarity ICE may not have any fuel/spark when initially doing so for regen purposes (so the ICE is spinning but not "running" under any gasoline based energy). However, the Honda engineers seem to have decided (for good reasons I think) to start the ICE to warm it up every time the cold ICE is spun up (maybe after the regen is no longer needed). Honda Hybrid ICE's are already running and warm most of the time (running except when the vehicle is stopped). Recall that the Clarity warm up rpm is about 1500 rpm, somewhat higher than a normal idle. So, even if the Clarity ICE is running, it may be running with a reduced throttle opening less than than needed for 1500 rpm so it still takes energy to spin it at a higher rpm.

    The Ford patent for dumping energy into the ICE coolant using a resistance heater is well known. There is limited heat capacity in the coolant so for continuous energy dumps, the vehicle cooling system would be needed to keep the coolant at a reasonable temperature. I wonder how the Honda BEV gets rid of excess regen energy when the traction battery is fully charged.

    My 1991 Toyota manual trans pickup truck stops the fuel when I take my foot off the throttle. The fuel flow starts again when the rpm goes below about 1200 rpm. It took me a while to figure this out and get used it when I first bought the truck 29 years ago. So, the idea of spinning an ICE (no fuel/spark) to provide engine braking (and reduced emissions) has been around for a while.

  20. insightman

    insightman Well-Known Member

    Thank you for clarifying. So if I understand you correctly, you believe the Clarity performs exactly like the i-MMD Insight and Accord Hybrid in that it uses the starter motor/generator turning the deadened ICE to absorb the excess regen energy that cannot go to the fully charged battery. Then, after using up that excess regen energy, the Clarity starts the ICE to warm it up. How long can the ICE delay starting up while the Clarity needs to continue dissipating excess regen energy?

    I believe people with OBDII scanners have observed the ICE is actually running when it fires up to deal with excess regen energy. I don't have a scanner, so the next time the ICE icon lights up on my display in response to the full-battery regen dilemma I'll stop the car immediately and feel the exhaust manifold.

    I wish Honda would just fess up on this matter. You might be correct, but I'd love to hear the story from their engineers.
    Last edited: Jan 1, 2020

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