Soooo. Will a Brake Buddy Classic work in a 2008 FEH?

 

Wow...the possibilities...

Leave the TOAD in gear, key on, and as you tow it the regen will recharge the hybrid battery, and thereby the 12 volt battery, as needed. Then just find a way to remotely actuate the brake pedal light switch.

If the hybrid battery becomes, or is, fully charged all wheels will roll freely as if in neutral.

http://cgi.ebay.com/ebaymotors/REMOT...mZ350390677996

Wireless remote fog light control is what I used to "open" the GPS/Nav DVD door to get rid of the "I agree" POS.

 

That's not possible Willard, the engine has to be started first before any gear is activated and there is no regen in neutral anyway.

GaryG

 

So, turn the "key" on, "start" the "engine" (ICE..?), and put the CVT into drive, and begin the "tow". The FEH "thinks" it's coasting downhill, shuts off the ICE, and then uses regen to charge the hybrid battery until full. Thereafter the FEH simply coasts along behind the MH until the brake switch activates. The hybrid battery is "full" so regen is not avaialble so the hydraulics are used.

 

It is my understanding of the CVT design and experience, once the FEH goes above 40MPH in Drive it has to run the ICE (I think the same or similar is required for the Prius CVT). Even if the engine is in fuel cut mode all that time, I don't think the wear caused by miles and miles of ICE idleing would be worth the benifit you mentioned.

 

I agree, I have little doubt that were the FEH traveling at higher speeds under its own motive power the ICE would be the primary provider. But in this case the FEH is effectively on the downslope of a steep mountain pass.

I would find myself really surprised if the ICE ran, provided DRAG, in fuel cut mode in any prolonged coastdown instance.

In point of fact it seems to me that the CVT would need to be in "B" mode even to begin using "fuel cut" mode wherein the drive wheels are "driving" the ICE rather than the other way around.

 

Willard, you're missing my point. Your idea for charging the battery just isn't worth the wear and tear of having the ICE turn while being towed (toad). I can tell you that even when going down a steep mountain above 40MPH in the FEH, in Drive with the switch on, the ICE has to spin. This has to do with the RPM limitations of the motors in the CVT and how the planetary gear works. Take a look at the PSD diagram on this page: http://eahart.com/prius/psd/ and you'll see that the Prius requires ICE RPM when speed exceeds 42MPG.

Beside, in your scenario, mileage will be, most definitely, added to the odometer. A side effect I'm sure almost every person towing would wish to avoid.

 

Exactly!

GaryG

 

Im get your point, but wouldn't that mean that shifting into neutral above 40MPH would require the ICE to rev up via some means...FUEL..??

 

According to the owners manual, the FEH can be towed in neutral, Key Off, safely up to 75mph. In this mode, the engine cannot and does not run or turn over even above 40mph.

MG1 controls the idle except in neutral. I shift to neutral as a FE technique in EV below 40mph and with the engine running above 40mph in the '05 - '08 FEH. The engine idle is not controlled by MG1 in neutral so the PCM takes over idle control with a little higher idle.

The '09 has complete fuel-cut above 40mph while coasting in "D" so there is no need to shift to neutral when the engine is running. During fuel-cut, the engine idle is controlled by the eCVT until acceleration when the fuel injectors resume providing gas again via the PCM.

GaryG