You can purchase an OBD-II device, which will report the engine RPM, but your Clarity has no way to display that number.
That's really good information @Atlantn. I thought that once it called for an "A1" then resetting the "1" would not change the date for the upcoming "A" service that was already signaled. So now this confirms, that yes, resetting "1" will indeed defer the "A" companion flag until the 12 month requirement, or whatever the next upcoming trigger would be.
I don't think from what I've read here that it takes work load into account at all. My first reminder just came on at 6000 miles and I run on HV three fourths of the time. Others who have burned just a tank or two of gas say theirs also came on at 6000 miles.
The conjecture that the MM "A" value comes on when any other service is needed (the numbered services) is supported by some other posts to this forum. I suspect that the tires need rotating every 6000 miles as on other Honda's (with specific tire rotation mileage requirements). So when the tires need rotating, the MM also shows an "A". Others have just rotated the tires and reset only the "1". Then the MM often went off and the next service time often then showed a one year time from the last oil change (for those that drive mainly in EV mode). The recent post in another section of this forum links to an SAE article specifically about the Clarity. In that article, the BSFC (brake specific fuel consumption ) is said to be calculated by the PCU to optimize that parameter of engine operation. The BSFC is calculated from the ratio of the fuel consumption rate to the power produced by the engine at any given time. The power produce is the engine workload (the power can be calculated from the engine rpm - air flow rate - VTEC settings- ignition timing - plus others mapping table if there is not a torque sensor in the power train). It is not unreasonable to think the the Honda engineers use this work load history for MM calculations (as is done and documented in the oil change monitoring by other manufactures). LeoP
That could well be, Leo. However, it appears that most, if not all triggers for the oil change "A" flag came about by the tire change demand as you noted. Everyone who reset the tire rotation saw the "A" oil change delayed by months, and typically to the 12 month anniversary of the car, when the oil should be changed no matter what. I don't think there has been any instances I can point to where an oil change came about purely by usage of the engine - at least that we can conclude. On our old CRV, it gives the oil life % estimate - if this car did it, I suspect that most would be in the 75-90% oil life by the time the 12 month necessary oil change comes up. But it is all just speculation on my part. I think someone had their oil chemistry analyzed and posted here somewhere.
LeoP So what explains the variability of the MM if it is set to remind folks to do a tire rotation at x miles? Owners report approx range of 6000 to 7500 miles when the MM light comes on? Other than odometer miles...what can the computer cipher on to recommend tire rotations...total revolutions? lol Since I am brand new to Honda...how does the MM work in traditional ICE vehicles? Does it recommend tire rotations and oil changes at the same time as well? Hard for me to connect the dots for the argument Honda makes a recommendation for tire rotation then, well you're at it...we suggest you change the oil too? Inquiring minds.
I know that I read somewhere on a Honda website (not Clarity specific) that the MM will try to aggregate sevices in order to reduce the number of service visits (and increase dealer profit?). This is supported by several posts that showed oil change intervals lengthened when tire rotation interval was reset. I think that’s pretty good proof.
Here's proof from one of their youtube descriptions of the MM system: (skip ahead to 2:22 where the concept is explained)
This is another good explanation of the MM logic, but it is slightly different as it is describing the Canadian system, which besides labelling everything in km, the routines are slightly different, and she describes the A / B routine where A service is the oil change and B is oil change, plus check brakes, various inspections, check fluids, and bunch of other stuff. For the US Clarity the routine is related but instead of "B" we have "0" (or really "A0" if you think about it), and she says the number codes are based off of mileage alone. Anyway, I think it allows us to peek under the hood and understand some of the MM logic.
I've read this whole post and others as well. My car is telling me to do a A01 service. My second at roughly 13000 miles. I drive mostly electric. If I just do a tire rotation, not at a dealer, and reset just the 1 portion of the MM, then my oil change will be delayed but not inappropriately so? I guess my question is rooted in that I do want to do my oil changes when I should so I don't want to try to delay the oil change in my car for it to not remind me when I actually should do it. Any help would be appreciated. EDIT: but I definitely don't want to do oil changes when I don't need to. Better for the environment and my wallet.
Thank you. I saw some logs from other members, and as I expected the engine RPM is not that high. It is in the same range as a 4 cylinder ICE car and I don't think the engine works really hard even in EV mode. I used to drive a 2006 Mazda3 manual and that car was running the engine around 3500 rpm on the highway. Not to mention Honda Civic Si or previous generation that could turn 4000 rpm on the highway.
Noticed my service soon is 8 weeks, putting me into March. Bought end of July and currently has 5500 miles, with less than 20 gallons total added. Never figured out my manufacturing date. At least dealer gives free oil changes for life and rotation is about $10
Look on the black info panel on the driver's door opening. Our Clarity was manufactured in October, 2017:
