gadgetman1

The other day I got a "Hybrid Battery Low" warning coming out of a car wash (vehicle in N). Has anyone had one of these? Is this a problem or a result of idling in town waiting in the car wash line with the A/C running full blast?

Sorry for the sideways pics - this crazy forum format turns my pics no matter how I format them

ggebhardt

When the hybrid batteries get down to one or two marks on the gauge, the gas motor should crank up to recharge the hybrid batteries.

I suspect that you battery was low from waiting in line and will in the tunnel it ran you battery down but the engine could not start because they had it in neutral and/or just the accessory turned on rather than the ignition. This would have prevented the engine from starting. Could have been just leaving it in neutral prevented the engine from restarting.

Not to worry, just the 450h telling you it is really low on juice.

gadgetman1

I'm sure it ran down some while waiting in line, but it was not a really long time (5-10 min). The car was running with me in it when the light came on (when I snapped the pics). I was hunting around the menus looking for the weather in my infotainment system several days ago & noticed in the maintenance section that "Hybrid System Failure" was listed for a date in March 2017. I had the car in for service in April 2017 & they never said anything about this. I wasn't overwhelmed by anyone in service, but it was 200% better than the non-service of my last vehicle.

ggebhardt

5-10 minutes with the AC and other things running will run the hybrid battery down for sure.

I would ask them for a reason for the "Hybid System Failure" for sure.

gadgetman1

I'm not asking how to recharge the battery. I'm asking why did it run down so fast.

NateJG

Really?

I thought you asked "...Is this a problem or a result of idling in town waiting in the car wash line with the A/C running full blast?..."

You then appeared to answer it yourself in post #3.

The MG1 provides the generation of electricity when the car is stopped - but only if there is a load provided by one of two things: 1) transmission in Park, or 2) transmission hooked to the wheels. Either of those two conditions will allow the MG1 to spin/generate.

If neither 1 nor 2 exist, then the planetary freewheels and the MG1 stays stationary - and allowing your air conditioner, blower, radiator fan, radio, WIndshield Wipers, 12v battery charger, steering, and displays to consume energy.

The dealer didn't report anything to you because there was, according to your post, no Fault to record/report.

"So fast" is more of a conclusion than it is a measurement - so it's hard to discuss.

https://www.clublexus.com/forums/hyb...-car-wash.html

Does this help?

gadgetman1

Yes & no. It explains a little, but raises more questions. If this is the longest that the hybrid battery lasts, I'm not impressed one bit with this car. Going thru a car wash in Texas on a 100 degree day is as routine as grocery shopping. If the battery won't last from one end of the tunnel to the other, this system is not engineered well or there is something wrong. Why wouldn't the engine come on instead of relying on the drained battery?

Also, why didn't the dealer say anything about the failure? I think that's important, especially if it kept that record in the maintenance log. Failure logging shouldn't be something routine & worry-free. I've noticed since the dealer serviced the car, that the fuel mileage has dropped considerably. I'm doing a lot more city driving & this thing is supposed to get close to 30 mpg in city driving. Right now, I'm getting 22 mpg at 12,000 miles. I think they screwed something up & it's time to go back.

ggebhardt

It is possible the engine will not turn on due to the vehicle being in neutral.

As as far as the batteries running down so fast, I do not think so. Everything is electric on the 450h and have the hybrid battery shut down after they reach a certain level is a safety feature that prevents harming the batteries. You did not check the hybrid battery before you pulled into the car wash, it might have been run down due to traffic before you pulled into the wash line.

No matter, I think it all worked they way it is surprised to and likely the engine being left in neutral had something to do with the engine not turning on. The drop in mileage in city driving is a worry and I would take it to the dealer for sure.

As far as the hybrid battery running down, am pretty sure it was because it was in neutral. That prevented the motor from recharging the hybrid batteries.

NateJG

You keep using the word Failure - when you haven't defined a failure.

When the car is not moving, MG1 is the ONLY way to start the car - and when the transmission is in neutral, there is no resistance for the MG1 to apply torque to turn over the ICE (aka start the engine).

You also appear to have a common (also my initial) misconception the design purpose of the hybrid system.

You dont have an electric car (like the Tesla) nor even a primarily-electric car (like Chevy's Volt) - you have an electric augmented car.

Your car recaptures and stores some of the kinetic energy by generating electricity during vehicle coasting/braking. It is then designed to AUGMENT the engine during acceleration. It (electricity) is never the primary mode of propulsion - however it can be temporarily and technically used to provide locomotion during very-light acceleration and also when cruising at low (under 40 MPH, for my model year) speeds.

I have never been able to go more than about 1.5 miles on battery alone - and those have been at speeds around 25 MPH.

Once you are past the "gee-I-want-to-see-what-it'll-do" phase, and simply drive the car like you've done in every other that you've owned, you will then come to appreciate that your car will deliver 30% better fuel economy than were you to be driving the comparable RX-350.

Oh, and when the dashboard tells you to take the car out of N, consider the instruction to be a feature and not a failure.

DunWkg

The manual says,
"Shift the shift lever to D when stopped at a traffic light, or driving in heavy traf-fic, etc. Shift the shift lever to P when parking. When using the N, there is nopositive effect on fuel consumption. In the N, the gasoline engine operates but electricity cannot be generated. Also, when using the air conditioning system,etc., the hybrid battery (traction battery) power is consumed."

I rarely, if ever, use neutral. That includes when driving to coast. No neutral coasting.

Do this experiment: park the car with engine running and in Park, turn on all electrical such as air conditioning, radio, lights and seat cooling, if you have it. The engine will catch up and it will stop. After a bit, the engine will start to charge hybrid battery. It will catch up and stop. The cycle will repeat. Keep your foot off of the accelerator, doing so forces the engine to run. If you want during the engine stopped portion of the cycle, push the accelerator and the engine will start. Lift your foot off the accelerator and the engine will usually stop.

If you watch the animation, you will see the battery charge and discharge. Neither fully charge or discharge, just modulate between the extremes.

If your experiment does not work as expected, head to Lexus service.

gadgetman1

I'm not sure why I'm not being clear here. I don't drive in "N" EVER. The only reason the car was in "N" was because all car wash tunnels require the vehicle to be in "N" in order to move the vehicle on the track. If the battery won't last thru a car wash tunnel, hybrid is somewhat of a joke to me.

I can't define "failure", because I have no idea what that means. That's not my word, it's straight from the Lexus screen on the dash. Why would Lexus put in a "Hybrid System Failure" log? It must be important...

I've tried to find out more info on the hybrid status meter, but haven't found anything. Sometimes the arrows are blue, sometimes yellow & sometimes red. Even the manual doesn't go into any detail on this. Older RX 450h have a different display.

NateJG

Is there a question still in there somewhere?

Or, perhaps, the concept of turning off your car during a car wash is just totally unacceptable to you?

Every car has a "feature" or "nuance" that either catches one by surprise or annoys - or even pleases.

You now know how to avoid this one.

DunWkg

In one of my manuals on page 125, it starts explaining the energy system as displayed on the multi-information display.

Sorry I thought you were waiting in line to get into the car wash. And no I have never, in three different hybrids, gotten that message. Granted, I don't use a pull-through car wash often, almost never.

Get it checked out, rather than get stranded.

gadgetman1

Have you ever turned off your RX 450h while in "N"? I tried it & wont do that again. All kinds of lights start flashing & nothing good comes of it.

ggebhardt

I think you just happened to pull in with a low hybrid battery and then the line ran it down farther and when they left the ignition on but put it in neutral, that was the end.

I use the same type car wash every week and never had this happen. Likely it was a one time event. Never happened in the past has it?