ICE runs after going down a hill at the beginning of my drive.

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Its possible that I did not really get any regen past a certain point and that the displayed range is lying to me, based on the fact that a normal 14kwh charge as reported by my juicenet charger changed it to say 68 miles range instead of the expected 50-52 miles range from that amount of charge. This would be similar to people getting a displayed range of 700-800 miles for the ICE after several gas fills. Probably a software bug... I would speculate that disconnecting the 12V battery might reset that???
 
Sound right to me. Went out today. Selected 4 bars. Stayed there. After about 1 mile ICE came on and stayed on for about 2 miles. Sport mode.
 
This must be the answer:

When the Moon is in the Seventh House
And Jupiter aligns with Mars

It's the Age of Aquarius. What else makes more sense? Happened again today.
 
Yeah it happened again to me a couple of days ago also. The only pattern I see is that the car was not driven yet that day each time I have seen it.
 
Found this in user manual page 15:

When the High Voltage battery is sufficiently charged, the vehicle is propelled solely by the electric motor. When the remaining power of the High Voltage battery drops to a certain level, the vehicle switches to HV.
 
Regarding:
"I can tell you for a fact that for me immediately after a full charge I always get limited regen for at least the first 3-5 miles or so in EV, shifter initiated regen blinks and reverts to 2 bars and brake pedal will not increase the amount of regen as it normally does.
Again, we all assume it’s to protect the battery from overcharging"

My 2008 Prius battery management operates in an analogous (sort of) way to high charge level.
When the battery gets charged too high (from soft driving and lots of coast) and then I have a long decelerate, it will burn battery power by spinning up the engine to 2500 RPM with the valves closed and fuel off.
Toyota's battery management hits the wall and opens the waste-gate.
Painful to watch the waste, so I try to anticipate and consume battery for drive.
 
From 2018 Chevrolet Volt Manual

In Electric Mode, the vehicle does not use fuel or produce tailpipe emissions. During this primary

mode, the vehicle is powered by electrical energy stored in the high voltage battery. The vehicle can operate in this mode until the

battery has reached a low charge.

There are some conditions when the battery charge is high enough to

provide Electric Mode operation, but the engine still runs. They are:

  • . Cold ambient temperatures.

  • . Hot or cold high voltage battery temperatures.

  • . The hood being open or not completely closed and latched.

  • . Certain high voltage battery fault conditions.

  • . Engine Maintenance Mode or Fuel Maintenance Mode being run.

This seems to be what the Clarity is doing insofar as Engine Maintenance Mode, but the manual does not mention regen as an issue.
 
More from Volt manual:

EMM runs the engine to keep it in good working condition after approximately six weeks of no or very limited engine operation. EMM will force the engine to run, even if there is a charge to power the vehicle.

FMM tracks average fuel age. Old fuel can cause engine problems. If low engine usage causes average fuel age to exceed approximately one year, FMM will run the engine to use up the old fuel…

Not every other day, or every day as the Clarity does if, in fact, it is EMM causing ICE to come online. The culprit seems to be either faulty software or bad design of regen.
 
Atkinson said:
When the battery [in my Prius] gets charged too high (from soft driving and lots of coast) and then I have a long decelerate, it will burn battery power by spinning up the engine to 2500 RPM with the valves closed and fuel off.
Click to expand...
That's what the Accord Hybrid does, too, but there's yet to be any confirmation that the Clarity PHEV uses this technique to burn off unwanted excess electricity being generated by its traction motor as the car decelerates. In fact, many on this forum report that the Clarity PHEV with a fully charged battery reacts to a regen situation by STARTING its engine. Curious, very curious.
 
Yes, Clarity starts the engine. From the Claritiy manual:

Auto Engine Stop/Start

The car will select the appropriate source of power depending on the drive mode you select.
As a result, the engine will automatically start or stop as needed to either charge the battery or provide supplemental power. Under certain circumstances, the engine may turn on or, if it is already on, it may not turn off.

● You are going uphill or accelerating aggressively.
● The climate control system is in heavy use.
● The Ambient temperature is too hot or too cold.
● The High Voltage Battery state of charge is very low.
● The vehicle is running a system check.

Nothing about regen.
 
bobcubsfan said:
More from Volt manual:

EMM runs the engine to keep it in good working condition after approximately six weeks of no or very limited engine operation. EMM will force the engine to run, even if there is a charge to power the vehicle.

FMM tracks average fuel age. Old fuel can cause engine problems. If low engine usage causes average fuel age to exceed approximately one year, FMM will run the engine to use up the old fuel…

Not every other day, or every day as the Clarity does if, in fact, it is EMM causing ICE to come online. The culprit seems to be either faulty software or bad design of regen.
Click to expand...

Thanks, I was going to ask whether the run cycle for injector purge was a factor!
Looks like is not.
 
insightman said:
That's what the Accord Hybrid does, too, but there's yet to be any confirmation that the Clarity PHEV uses this technique to burn off unwanted excess electricity being generated by its traction motor as the car decelerates. In fact, many on this forum report that the Clarity PHEV with a fully charged battery reacts to a regen situation by STARTING its engine. Curious, very curious.
Click to expand...
As a test, maybe an affected driver could try charging to not more than 80% to see if the engine starts.
Assuming ECO on, Sport off, Heat and AC off, efficient driving, etc.
 
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