Clarity Won't Start - No Power

Any condition outside of a manufacturers specification for operating or charging can be detrimental to the battery.

FWIW: We have a bank of L16 FLA’s for solar energy storage at the house. They are 10 years old, have been kept “topped off” for 98-99% of their life, been through a few dozen charge cycles, had water checked/added every 3-6 months and have had an equalization performed annually. They still have more than 90% of their original rated capacity based on actual “off-grid” loading and monitoring to the tenth of an Ah of energy consumption.

 

Since the red 12V battery icon was not illuminated I would think this confirms that your car was using the HV battery via the DC-DC converter to provide 12V power to the car, it was not draining the 12V battery. Why you would see less than 12 volts during this time doesn't seem to make much sense as that would seem to be contradictory information between what the display is telling you and the voltage reading that you are seeing.

Not sure what you mean by "your car was still plugged in when it let you go into ready mode?" I already had it in READY mode, then I got out and plugged in the charger. I thought that was the situation that you are describing, someone forgets to turn off their car (thus leaving it in READY mode) then they plug in and walk away not realizing the car is still on. If you plug in while the car is in READY mode, it switches to the modified version of ON, i.e. the READY indicator goes away, the display says to press the power button and the brake to start the car, but the red battery warning icon is not displayed, and in my case anyway I see 14V indicated in Car Scanner.

 

I don't quite understand what situation you are describing, or what people are doing at the EV discovery center that causes their car to be inadvertently left in ON mode. Do you mean they are plugging in their cars to charge there but leave the car turned on, and that is draining their 12 battery? If so then I guess their EV's work the same way that your Clarity apparently does, and not how my Clarity works.

When I said people often drain their batteries in ON mode I am talking about normal ON mode (not plugged in) where someone thinks they are turning on the car, but they fail to press the brake pedal so it goes into ON mode which will drain the 12V battery. Why someone would do this can vary, they may have turned off the car when they parked, then decided to turn it back on to run climate while they check emails or wait for someone or whatever. Or I think an easy way it could happen is that someone turns off their car and gets out, then decides that they want to turn it back on and leave it on with climate running while they are out doing whatever. Even though they can't lock the doors while the car is running they are presumably in a situation where they aren't concerned about this. So they open the door and reach in to press the power button, forgetting that they also need to press the brake pedal. The first button push doesn't seem to work so they press it again, the instrument panel lights up and the car looks like it has turned on and they hear the fan running, but fail to notice the red 12V battery warning icon and the fact that READY is not displayed. They walk away then come back later to find the battery is dead.

I am not aware of the Volt working this way. The Clarity (and I assume the Volt) will turn on the engine only when you are in READY mode. If you are sitting parked in your Clarity in READY mode and your EV range drops to 0 miles, then it will start up ICE to recharge the HV battery. It actually does this below 0 miles, as 0 miles is 10% SOC and while sitting parked the engine will not usually come on until you are down to around 1% SOC, although on the display it still says 0 EV miles since it will not display negative miles. When the engine starts up it only recharges to around 3% then shuts off again. Repeating this cycle of ICE turning on and off as long as you leave the car sitting in that condition (again this is only in READY mode). I would think the Volt does something in that situation.

Neither car will start the engine to charge the 12V battery, because the 12V battery is charged by the HV battery via the DC-DC converter. Now as I mentioned if the Clarity HV battery gets down to about 1% in READY mode it will fire up ICE , but that's to charge the HV battery not the 12V battery, which shouldn't be getting low anyway since the 12V battery gets charged (when needed) by the HV battery as long as you are in READY mode. I would think the Volt works similar unless you have some different information.

 

You obviously do not live in Phoenix AZ.

 

So I am talking about people jsut leaving the car in 'ready mode' and walking away, not plugging it in, jsut leaving it in park and walking away with it fully on.

According to the people at the EV discovery center the clarity WILL NOT run the ICe engine when in park and left on. It literally does what the OP mentioned his clarity did when they jumped it. fired up the ICE engine at an insane rev to recharge the traction battery that was at '0' (or rather 10% but you know what i mean). This means that the clarity totally drained the traction battery, then drained the 12v and did not fire up the ICE as there was still plenty of gas in the tank

 

As others have pointed out, the Dc-DC converter is not always charging the battery even when driving. it does not mean the red battery light will go on just because it's not charging. The only way to determine if it is charging or not is to check the voltage. I think the red light jsut indicates that the DC-DC converter is powering the 12v system or not.

You mentioned that after plugging it in, if you press teh brake and press power you can return it to ready mode and you did not mention if you unplugged yoru car or not. Taht was what I was asking.

 

So we have to take the discovery center's word on it that the cars that have this problem were always in READY mode. Were they plugged in when this happens? And why is everyone there walking away with their cars running?

Not trying to argue all of this I'm just perplexed that all of these cars including yours seem to work differently than mine. More than once I have sat in my car with it running, it never drains the 12V and if SOC gets down to 1% it starts up ICE.

Only difference I can think of is that I never leave my car when it is running, I am always sitting in it. Maybe the presence of the keyfob in the car makes a difference in these situation.

 

Looks like the big discovery at the EV discovery center was the revelation that turning the car off before walking away might be a good idea. Maybe they were hypnotized by an EMP when they entered the parking lot. Where is this place?

Doesn’t the car cry out for attention in some way if it isn’t turned off and the fob leaves the car? Bells ringing or it beeps 3 times if you try something wacky like locking the doors?

Drain the HV battery? Was this a weekend retreat? I once powered up, put in ready mode, turned on, started, fist pumped, belly bumped, dry rubbed, whatever it took, to turn the heater on full blast in order to partially drain the battery. I had a couple of juicers installing a 240V circuit for the new L2 device and wanted to test it out. It took a considerable amount of time to drain the battery about 1/3, and it nearly set the steering wheel on fire.

Now, while that gerbil driven engine may alarm some, it won’t rev beyond what the engineers have determined is safe for all components.

 

I think people missed the part where I mentioned that with the sheer number of people going through test driving the cars it's quite often when people don't turn it off since they are completely silent.

I don't think it takes a stretch of the imagination to imagine all these people who have probably never used that car before could mistakenly not shut it off espeically since it's silent, and usually the person is chatting up the other person who knows how to use the car distracting them. And I mean I've been there when they've had dead cars. It is factual that they were dead. How they got that way might be up to interpretation.

I've never drained my traction and 12 volt battery, but there definitely is a danger if one is prone to walking away from a silently on car in a one car garage for it to run the ice all night and the decision may have bene made to not let it do that. As for keyfob location I also don't think it's illogical to think that the car would think that the operator of the car is absent without the keyfob. They do allow operation of the vehicle for safety reasons without a fob signal but in park it might be safer to assume there is no one at the wheel you know? (again ice operation in an enclosed space unsupervised isn't ideal)

One of the more annoying things about the clarity is how it doesn't let you know when the car is on or the door is open and you try to lock it. It simply doesn't do/beep/flash anything, that's the only hint that something is not in perfect safe state is the lack of anything. (yes it does do teh 3 quick beeps right when you leave the car, but after that there is nothing even if you spam lock, unlock, etc. and those beeps arem't very loud. If you are taking in groceries and coming in and out you can easily forget that those beeps happened. or with kids running around screaming.)

I've found that the climate systems can draw around 2kw's of power based on measurements off the EVSE when climate is on for ac and it seems (I did not do an exact measurement) up to 4kw for heat. I know it does go down as it reaches the target temperature, but i've test driven those cars at the center before. They BLAST the AC and they are never fully charged. Even at a full brand new battery a 2kw draw will drain the clarity battery in about 7 hours (3.5 for 4kw), much less than the 17 hour span of an overnight stay for the car (plus also it's not like they test every single car right at open and you can't assume the clarity was the very last car to be tested and left on fully charged. Even with less of a climate draw, with a 40% battery it would still probably use enough power to die several times within 17 hours. I don't really understand how it is that difficult to see it's very possible. You can't really get past math and physics here. There is a reason why people turn down the temperature to squeeze out a few extra miles from EVs and even why preconditioning the cabin makes a huge difference to your range. Climate systems take alot fo energy.

 

Oh I forgot to add, the reasoning behind why they thought it was in ready mode is because the traction battery was completely depleted along with the 12v. (as I mentioned, they said the gas engine fired up immediately to charge up teh traction battery when they jumped it beucase it was 0(10% SOC) and it happens often enough that they have found the volt idling when they come to the center the next morning. The other car I know that they ahve found completely dead traction+12v was the leaf, but ti was partly beucase i was asking a lot about the leaf, volt and clarity that I got told stories about these cars and issues they've encountered.

 

@Frankwell @Landshark

I did a quick search of these forums and there are examples of otehr people finding the leaving the clarity on issue. This one killed their traction (down to two bars they say) and 12v in only 3 hours but still had the gas in their tank which let them drive away after a boost:

https://www.insideevsforum.com/community/index.php?threads/left-clarity-on-by-mistake-way-way-up-in-the-mtns-ohh-dear.2086/

I think it's safe to say the clarity does not fire up the ice if left on and i guess with no key fob

 

Must be a Canadian thing. Mine dings once if a door is opened in Ready mode. Not to mention the dash is lit up. The door chime is constant when opened in On mode. It beeps 9-10 times if you try to lock the door when it hasn’t been turned off.

It’s a little more tricky than a car where you turn a key and shut it down, but it isn’t rocket science. Honestly, if someone isn’t aware of whether or not a car is on or off, they shouldn’t be driving.

 

might be just canadian cars then or possibly firmware version? I tested it this morning. As long as it's in park my clarity doesn't make much more noise than one tone when you open the door with teh key fob inside (then nothing) if you close the door with the key fob outside the three beeps then the sound of silence. and nothing if you try to lock it like this, nothing if try you unlock it or really press any of the buttons, and when you open the door no sound.

 

It sounds as though there are some variations in audible alerts between US and Canadian models. That said, one tone is different than zero tones and 3 beeps is different than zero beeps. Now you are familiar with the alerts that the vehicle provides to the operator.

 

Long story short: My 2-month old 12-Volt battery died because we didn't drive our Clarity enough.

Long story long: The Clarity displayed a strange symptom and I tried this bunch of stuff before finally hooking up a battery charger to get going again:

Two months ago my dealer installed a new battery in our 2018 Clarity with 14,000 miles on the odo. We've driven our Clarity PHEV a few times since then, but not in the last week. Today, when I tried to start the Clarity, it made the start-up sounds but the dash never lit up and the Power button started pulsing red and wouldn't respond to additional presses. Holding the fob against the Power button didn't make a difference.

The Clarity Owners Manual doesn't describe the pulsing Power button in the "Power System Won't Start" section. I turned to the section titled, "Emergency Power System Off," which reads:

• Press and hold the POWER button for about two seconds.
• Firmly press the POWER button three times.

That procedure had no effect. The Power button continued to pulse.

Pressing the charge-lid button caused a loud click, but the charge-port door wouldn't open. None of the fob buttons had an effect. When I got out of the car, the Clarity sounded "you're getting out of the car without turning it off" warning. I returned 10 minutes later and the Power button was still pulsing red about once a second.

I took the second fob into the car and pressed the pulsing Power button again. That caused the "you're getting out of the car without turning it off" warning to sound, but nothing else happened. The warning didn't sound again with subsequent presses of the Start/Stop button. The Clarity wouldn't react to any of the second fob's buttons.

I opened the charge lid by pulling the manual charge-lid release lever under the dash. The Power button stopped pulsing and went dark. Nothing happened when I plugged in my EVSE. Now I wish I had tried plugging in the EVSE while the Power button was still pulsing. Maybe there was a chance it might have started charging both the traction battery and, in turn, the 12-Volt battery.

A year ago the original battery went dead after not driving the Clarity for two months. Due to interference from garage shelves hanging over the hood, I had to crawl along the floor on the right side of the floor to attach a battery charger. Fortunately, I didn't park the Clarity so close to the right side of the garage this time so I didn't have to crawl next to the car after opening the hood 6 inches and propping it up with a cardboard box.

I charged for two minutes, disconnected the battery charger, and the Clarity started--without the usual fireworks display of multiple warnings that usually accompanies a 12-Volt battery reset. I turned it off and tried starting it again. The two-minute charge was exhausted and I got the pulsing Power button again. I plugged in the EVSE, but no dice--it didn't begin charging.

After an hour of charging the Clarity powered up and the multi-system instrument panel fireworks display commenced. The TPMS system needed to reset, as did the vehicle stability system. The recalcitrant Clarity didn't want to back out of the garage, displaying the message "Gear Unavailable. Try Again After Awhile." Awhile later, I was able to back out and go for a short drive. As always, I hated the sound of our neglected Clarity's rusty rotors going swish-swish-swish even when I wasn't using the brakes and swishing louder when I was turning a corner.

I was happy to discover the radio-station settings didn't go away. I was unhappy to discover I couldn't lower the rear windows from the driver's armrest console. I parked, reached back, and found the rear windows would respond to their own switches. After that, the rear windows would respond to the switches on driver's armrest console.

Upon returning from my short drive, I plugged in the Clarity and it was happy to begin charging. The battery had about a 75% charge before this get-to-know-your-Clarity Saturday.

I'm still unclear what the pulsing Power button display is supposed to indicate. Is the car saying "I have just enough power left to avoid a 12-Volt reset if you charge my battery now" or is it just telling me "My 12-Volt power is all but gone--I have just enough left to signal 'Goodbye cruel world'"?

I can think of two options for preventing this problem from re-occuring: stop choosing our MINI Electric over the Clarity for every short excursion (ie. every excursion these days) or install a battery-tender cable I can access without raising the hood.

 

I had this happen a few months ago with the driver side rear window. Same maneuver fixed it. Initial thought was they’ll probably have to replace the entire wiring harness like they did for the member who had a malfunction daytime running light.

There’s something else going on with your car, or Honda installed a defective battery. As reported previously, I’ve left the car to sit for 4-6 weeks on at least 2 occasions and the 12V was not dead either time. If you drove it a week ago the 12V should not be depleted.

The only time my 12V was dead was when the car sat for 6 months. I jumped it with a lithium pack, drove it about 20 miles, yes I know, there’s no need to drive it, turned it off and back on upon my return, drove to work the next day and haven’t had an issue starting the car since. That was Sept of 2020.

 

My Clarity sits in a Battery Tender Plus now after I had EXACTLY the same thing happen to me. Luckily for me I can full open the hood so it wasn’t as hard to figure out as yours. The battery eye was White/red indicating charge needed. It took the tender about a day to get it where it started up and then it kept indicating full while the batter still indicated charging was needed. I took it out and drive it around for a while since it had been sitting and then left it on (set a timer) for an hour and it finally flipped to blue/red. My battery though is still the one I got in the car 3/18. Not ready to replace it yet lol.

 

Interesting. I have a May build 2018 (35k miles) that has never had a 12V battery issue and I have gone at least a couple of weeks without driving on multiple occasions. I do have a jump start pack and jumper cables in the storage area in the trunk, but so far no need for them. I'm going to run the 12V battery until it fails, but wouldn't be surprised if it lasts for at least a couple more years.