Warning To Shift Into Park To Charge Battery While In Neutral

[r6264]

While in the car wash today, I had my 2007 RX400h in neutral.

Half way thru, a warning began to flash stating that I had to put the vehicle into the park position to charge the battery.

I might add that the headlights, air cond and radio were on.

When I got home, I checked the battery and it looked fully charged and up to par.

Anyone have this problem??

[cduluk]

I've gone through the car wash several times with my Rx400h in neutral and never got any such warnings. Any chance the car's still under warranty?

[katzjamr]

i think it is just a warning not to leave it in the neutral position for long periods of time as the battery will run down and not charge. am i right on this people? going through the car wash in neutral is no problem.

[maseace]

When you shift into N, the hybrid system leaves the gas engine in whatever state it was in before shifting into N. If the engine was not running, it would stay off in N, so the hybrid battery would not be able to recharge when it got low. If the engine was running, it would stay on while in N and waste gas. At least that's how the HSD system works on the Prius, and I believe the RX400h system has the same design.

[BobBass]

Funny....this happened to me for the first time the other day. We had been waiting in line to get in the car wash and since the A/C was on while sitting there, the traction battery charge dropped. By the time we actually started to go thru the wash, when I put it in neutral, I got that same warning. However, when I shifted to "D" at the finish, everything was fine.

BTW, I recommend you do NOT have the HVAC on while going thru a car wash. Dunno if it's the same design as a Camry, but we did that one time with our TCH and water got in the air intake and saturated the cabin filter. The A/C was very weak until the filter dried out.

[lemon]

When you shift into N, the hybrid system leaves the gas engine in whatever state it was in before shifting into N. If the engine was not running, it would stay off in N, so the hybrid battery would not be able to recharge when it got low. If the engine was running, it would stay on while in N and waste gas. At least that's how the HSD system works on the Prius, and I believe the RX400h system has the same design.

No. From the shop manual - "When in neutral, MG1 and MG2 are shut down. This is because MG1 and MG2 must be stopped electrically as a means of shutting down the motive force, since MG2 is mechanically joined to the front wheels. On the 4WD model, MGR is shut down as well."

So what this basically means is MG1 is shut down in neutral because MG2 is connected to the front wheels and in neutral you don't want any power going to MG2 from MG1 since you don't want the wheels to be powered. However, MG1 also charges the battery as well as powering MG2, so it can't charge the battery when in neutral because it's shut down so it doesn't power MG2.

Clear as mud?