Battery Issues

[MyToys]

The other day for the 3rd time I hoped in my 400h and went to start it and nothing, the first time this happend was at the dealer. As I was purchasing slightly used I thought little about it they jumped it and away I went. The second time was in my driveway and really can't understand why about that one unless one of my kids left door slightly ajar which could of happend. Now this third time we had my son at swiming lessons for 45 minutes parked in spot directly next to pool with shaded bench in front of car, I must admit I left keys in car but WERE in off position, nothing was on, 45 minutes later jump in won't start againg.

So seems too me I have battery problem, I just finished my 15K service but suspect that means they just check water level in battery. So will Lexus do any for me? Is this normal? I have heard the Hrbrd battry's last short time but this seems like more of a problem than than. Input would be welcome.

Mark

[Gryphon]

Mark, the starter battery in the RX400h is somewhat small but I assume adequately sized for it's purpose of starting a small V-6 engine. The correct way to diagnose the condition of your battery is to fully charge it (best done with a AC charger, not by driving) then do a load test. Almost any place that sells batteries has a load tester, although many have inexperienced kids working there who are not well trained.

Tom

[skyfish400h]

The other day for the 3rd time I hoped in my 400h and went to start it and nothing, the first time this happend was at the dealer. As I was purchasing slightly used I thought little about it they jumped it and away I went. The second time was in my driveway and really can't understand why about that one unless one of my kids left door slightly ajar which could of happend. Now this third time we had my son at swiming lessons for 45 minutes parked in spot directly next to pool with shaded bench in front of car, I must admit I left keys in car but WERE in off position, nothing was on, 45 minutes later jump in won't start againg.

So seems too me I have battery problem, I just finished my 15K service but suspect that means they just check water level in battery. So will Lexus do any for me? Is this normal? I have heard the Hrbrd battry's last short time but this seems like more of a problem than than. Input would be welcome.

Mark

Take it back and ask the dealer to diagose and repair it. You should not be having this kind of problem.

[SOMEONE ELSE'S GOT MY NAME]

Mark, the starter battery in the RX400h is somewhat small but I assume adequately sized for it's purpose of starting a small V-6 engine. The correct way to diagnose the condition of your battery is to fully charge it (best done with a AC charger, not by driving) then do a load test. Almost any place that sells batteries has a load tester, although many have inexperienced kids working there who are not well trained.

Tom

Errr, the smalll battery doesn't 'start' the hybrid system ... the hybrid pack runs most all functions. Our 400h hybrids don't have a starter motor. The little battery mearly boots up the onboard computers, which then send the proper signals for turning the ICE on ... when necessary. In fact, you can even hook up a few flashlight batteries to boot up the system. The dealer ought to be able to tell you whether the car's battery is bad, or whether there is something not turning off (dome lights, etc) that drains the battery.

[RXREY]

What is "ICE" that I keep seeing in many posts?

[katzjamr]

ice is internal combustion engine

[williz]

The other day for the 3rd time I hoped in my 400h and went to start it and nothing, the first time this happend was at the dealer. As I was purchasing slightly used I thought little about it they jumped it and away I went. The second time was in my driveway and really can't understand why about that one unless one of my kids left door slightly ajar which could of happend. Now this third time we had my son at swiming lessons for 45 minutes parked in spot directly next to pool with shaded bench in front of car, I must admit I left keys in car but WERE in off position, nothing was on, 45 minutes later jump in won't start againg.

So seems too me I have battery problem, I just finished my 15K service but suspect that means they just check water level in battery. So will Lexus do any for me? Is this normal? I have heard the Hrbrd battry's last short time but this seems like more of a problem than than. Input would be welcome.

Mark

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

[SOMEONE ELSE'S GOT MY NAME]

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

I believe the charge system has another unique feature. Presuming you CAN get enough volts to "power up" the system, the car's hybrid batteries will supply current to recharge the car. Thus, if you merely leave the system in ready mode, power will be resupplying the 'boot-up' battery.

Edit: BTW, we've never left the rear lid open (purposely or accidentally) for any length of time where the dome light drain would be an issue, but I thought it would "time-out" after so many minutes, then turn off. Our Prius does, as do many other cars. Just like the headlights Not the case w/ Lexus dome light? Guess I'll read up on that, too.

.

[williz]

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

I believe the charge system has another unique feature. Presuming you CAN get enough volts to "power up" the system, the car's hybrid batteries will supply current to recharge the car. Thus, if you merely leave the system in ready mode, power will be resupplying the 'boot-up' battery.

Edit: BTW, we've never left the rear lid open (purposely or accidentally) for any length of time where the dome light drain would be an issue, but I thought it would "time-out" after so many minutes, then turn off. Our Prius does, as do many other cars. Just like the headlights Not the case w/ Lexus dome light? Guess I'll read up on that, too.

.

yes, as soon as the car is in the "ready" mode the 12V battery gets charged but my point is that it gets charged with 13,9V and with this voltage a 12V battery never gets fully charged. to fully charge a lead acid 12V battery it needs 14,5V.

i like to find out if only my car is charging the 12V battery with 13,9V and this is the reason why i had so often to jump start it.

the doom lights turn off after about 30 minutes if you leave the back door open. the funny thing is that this sometimes is enough to bring the battery below 12V and you need to jump start your car. some day i came back to my car and the alarm system was on for some time (horn was sounding). guess what? i had to call assistance to jump start the car, battery was to low.

[riwyle]

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

I believe the charge system has another unique feature. Presuming you CAN get enough volts to "power up" the system, the car's hybrid batteries will supply current to recharge the car. Thus, if you merely leave the system in ready mode, power will be resupplying the 'boot-up' battery.

Edit: BTW, we've never left the rear lid open (purposely or accidentally) for any length of time where the dome light drain would be an issue, but I thought it would "time-out" after so many minutes, then turn off. Our Prius does, as do many other cars. Just like the headlights Not the case w/ Lexus dome light? Guess I'll read up on that, too.

.

yes, as soon as the car is in the "ready" mode the 12V battery gets charged but my point is that it gets charged with 13,9V and with this voltage a 12V battery never gets fully charged. to fully charge a lead acid 12V battery it needs 14,5V.

i like to find out if only my car is charging the 12V battery with 13,9V and this is the reason why i had so often to jump start it.

the doom lights turn off after about 30 minutes if you leave the back door open. the funny thing is that this sometimes is enough to bring the battery below 12V and you need to jump start your car. some day i came back to my car and the alarm system was on for some time (horn was sounding). guess what? i had to call assistance to jump start the car, battery was to low.

Maybe you are only seeing the float charge, for which 2.3v per cell is proper. You should measure the open circuit voltage to determine the state of charge at that time (unfortunately it is not possible to measure the specific gravity). Since this battery never has to turn a starter motor, as with a conventional car, it should never be drawn down and maybe the float charge is all it needs. Would be interesting to see the complete wiring diagram and a description of the charging logic to understand what is going on causing the reported "dead" batteries.

[jerryray]

The other day for the 3rd time I hoped in my 400h and went to start it and nothing, the first time this happend was at the dealer. As I was purchasing slightly used I thought little about it they jumped it and away I went. The second time was in my driveway and really can't understand why about that one unless one of my kids left door slightly ajar which could of happend. Now this third time we had my son at swiming lessons for 45 minutes parked in spot directly next to pool with shaded bench in front of car, I must admit I left keys in car but WERE in off position, nothing was on, 45 minutes later jump in won't start againg.

So seems too me I have battery problem, I just finished my 15K service but suspect that means they just check water level in battery. So will Lexus do any for me? Is this normal? I have heard the Hrbrd battry's last short time but this seems like more of a problem than than. Input would be welcome.

Mark

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

I just looked at the scangage web page. That device uses the OBII socket.

It is possible the battery voltage AT THE BATTERY may be higher than the connector shows, depends on what the current load is at the OBII side. If you have a digital voltmeter please veriify by taking an actual reading from the battery.

13.8 is a float voltage used on many standby batteries. Since the main battery does not start the car, could be one reason they run it lower.

My battery is usually 13.8 to 13.9 volts.

[williz]

The other day for the 3rd time I hoped in my 400h and went to start it and nothing, the first time this happend was at the dealer. As I was purchasing slightly used I thought little about it they jumped it and away I went. The second time was in my driveway and really can't understand why about that one unless one of my kids left door slightly ajar which could of happend. Now this third time we had my son at swiming lessons for 45 minutes parked in spot directly next to pool with shaded bench in front of car, I must admit I left keys in car but WERE in off position, nothing was on, 45 minutes later jump in won't start againg.

So seems too me I have battery problem, I just finished my 15K service but suspect that means they just check water level in battery. So will Lexus do any for me? Is this normal? I have heard the Hrbrd battry's last short time but this seems like more of a problem than than. Input would be welcome.

Mark

you are not the only one having this kind of problems!

here in europe many RX400 users are complaining about the same "battery dead" situation. when we started to look into that we all assumed that the small 12V battery is the source of the problem.

situation is that it takes only about 45 to 60 minutes with the interior light on and you can not start the car again. this happens easily also when you leave the back door open after offloading your car in the garage.

after installing a scangage II (www.scangage.com) in my RX and observing the 12V voltage i found that the charging voltage is never higher than 13,9V. tho fully charge a 12V lead battery you need 14.5V. this means that my car (and so far i can only speak from my car only) is never fully loading his 12V battery. actually it is not charged for more than 50% of its full capacity.

i will do the 45.000km service next week and will confront the lexus service personell with this finding. looking forward to see what they will tell me.

i am very interested to see if only my car is loading with only 13,9V. have anyone measured his 12V power when the car is in "Ready" state?

regards

williz

I just looked at the scangage web page. That device uses the OBII socket.

It is possible the battery voltage AT THE BATTERY may be higher than the connector shows, depends on what the current load is at the OBII side. If you have a digital voltmeter please veriify by taking an actual reading from the battery.

13.8 is a float voltage used on many standby batteries. Since the main battery does not start the car, could be one reason they run it lower.

My battery is usually 13.8 to 13.9 volts.

i check t the voltages with a digital voltmeter today on two cars (RX400h's model 2006).

charging voltage is definetly 13,8 to 13,9V.

battery voltage without charging and internal lights on is between 11,4 and 12,4 volts. if i am right this would mean a nearly empty battery?!

[SOMEONE ELSE'S GOT MY NAME]

Being inquisitive & profound like I am ( :P ) I made a treck to the dealer and asked the tech. He said it's designed only to trickle charge as it's not deep discharged as a starter battery is. Ok it wasn't a treck for that question really. It was for an alignment to keep our brand new Michelins perfectly perfect. But since I was at the dealer anyway ... that WAS the tech's response.

[jerryray]

i check t the voltages with a digital voltmeter today on two cars (RX400h's model 2006).

charging voltage is definetly 13,8 to 13,9V.

battery voltage without charging and internal lights on is between 11,4 and 12,4 volts. if i am right this would mean a nearly empty battery?!

After turning the car off, the battery should be at least 12-13 Volts. 11.4 is not good, perhaps something is drawing current that should not.

Any aftermarket alarms, stereo's installed.

Time to have the Lexus techs check it out.

[NY_RX400h_Savanah]

Well the problem again is in design-go to you nearest BMW or MB dealer -get the keys- leave any lights you want inside on-as soon as you lock the car with the alarm-all of them will go off. That's the way it should be-why the hell you'd leave any interior light on while the car is armed already???. See the problem is that german cars use "interlock logic switches" to get any lights on or off (basically you touch once you get light on, you touch twice it goes off-like power button in newer TV's i.e.)as oppose to manual ON/OFF switches that Lexus uses (like power switch in old TV's). With interlock logic- anything you want (alarm arming i.e.) can reset intelock state and in that case turn your light off-in Lexus since it's all mechanical-nothing you can do. Pretty stupid considering that in hybrid's case every time your battery goes dead-dealer has to re-initialize your system for proper hybrid operation.And guess what 7:15 tomm. morning I have to drive to dealer to do it because kids left lights in the back on when we parked during the day-second time in 2 years. Considering how advance hybrid system is-they've dropped the ball here big time.

[RX400h]

One of us had left a door ajar (RX400h) for the entire night and the engine had no issue getting started the next morning. Of course, the light was automatically turned off long before battery voltage could drop to dangerous levels. Therefore, I don't think the Lexus electrical system is as simple as you think.

[NY_RX400h_Savanah]

One of us had left a door ajar (RX400h) for the entire night and the engine had no issue getting started the next morning. Of course, the light was automatically turned off long before battery voltage could drop to dangerous levels. Therefore, I don't think the Lexus electrical system is as simple as you think.

:) good joke- turn on you two switches on the side of shift switch in front (by moon roof controller) and leave your car overnight-than get back and say what happened. Lights you said you left on are the ones you can shift from ON to OFF to DOOR-if you leave them OFF- of course your other lights in the car will go off after period of time-leave them ON and see what happens.

PS

I didn't say electrical Lexus system is simple-I said it's a simple design to fix the issue but Lexus didn't do it-that's simple.

[Gryphon]

This is a sore subject with me. On several occasions I have left an interior light on overnight. In each case I discover what appears to be a completely discharged auxiliary battery and a car that won't start. Yes, my bad, for leaving a light on, but Lexus' bad for a really crappy electrical design. Why do I criticize? Because.........

1. The rear hatch is mysteriously inoperative, manually or otherwise.

2. The radio loses it's presets.

3. The map reverts to east coast instead of my local area, Arizona.

4. The seat memories are lost.

5. The windows (some but not necessarily all) become mysteriously inoperative after recharging the battery and must be "retrained" to work by operating each of them with their respective buttons on each door.

And, to rub salt into the wound, the vehicle will not accept a jump start because the computer is "protecting" something. Yes, I know that some of you have talked about jump starting, but my car simply will not do so. I have discussed this with a Lexus roadside assistance expert, and he has confirmed that this is a design issue, not my inability to properly use jumper cables. (Supposedly the aux battery is not really completely dead, but has been shut down to protect the drive batteries. And, yet, it can't seem to find a way to provide just enough juice from either battery to start a small gas engine.)

Perhaps I just expected too much for my $50,000.

Tom

[NY_RX400h_Savanah]

This is a sore subject with me. On several occasions I have left an interior light on overnight. In each case I discover what appears to be a completely dischaged auxiliary battery and a car that won't start. Yes, my bad, for leaving a light on, but Lexus' bad for a really crappy electrical design. Why do I criticize? Because.........

1. The rear hatch is mysteriously inoperative, manually or otherwise

2. The radio loses it's presets.

3. The map reverts to east coast instead of my local area, Arizona.

4. The seat memories are lost.

5. The windows (some but not necessarily all) become mysteriously inoperative after recharging the battery and must be "retrained" to work by operating each of them with their respective buttons on each door.

And, to rub salt into the wound, the vehicle will not accept a jump start because the computer is "protecting" something. Yes, I know that some of you have talked about jump starting, but my car simply will not do so. I have discussed this with a Lexus roadside assistance expert, and he has confirmed that this is a design issue, not my inability to properly use jumper cables. (Supposedly the aux battery is not really completely dead, but has been shut down to protect the drive batteries. And, yet, it can't seem to find a way to provide just enough juice from either battery to start a small gas engine.)

Perhaps I just expected too much for my $50,000.

Tom

Well just had it all done today-you also forgot to add ISC calibration-otherwise you'll get crappy milage and hard engine cuts.

Should it be sore for you??- Of course. Service is free under warranty- but come on- do it every time your kid forgets to turn the lights off or when even you do it. And honestly-someone please explain to me-WHAT IS THE POINT OF HAVING INTERIOR LIGHTS ON AFTER YOU ARM YOUR CAR WITH THE ALARM??? Besides- a circuit with relay disconnecting all unnecessary devices when battery goes dangerously low would cost about $10

[Gryphon]

I have never heard of ISC calibration. Please explain?

Tom

[Jim Nazium]

I have never heard of ISC calibration. Please explain?

Tom

Apparently if you disconnect the battery or the battery discharges too low you require going to the dealer to recalibrate your ECU. It is said that the ECU requires to be properly configured or else your vehicle initial mileage will suffer. The service rep seems clueless if you ask for "ISC calibration", and I cannot vouge for sure whether it is really required or not.

I read somewhere there is a TSB and procedure one can do to calibrate the ISC. I personally find it a little extreme in nature and have not attempted it myself more than once.

I did have the dealer "set" or "reset" my vehicle once when I disconnnected the battery and recharged it (unknowingly of course) and asked them about the "ISC calibration". I don't know if it was done or not, but whatever the mechanic did perform did return full functionality to all the individual "electronics" that would otherwise not work properly (i.e. the garage door opener, power windows, seat memory etc.).

Cheers,

MadloR

[Jim Clark]

I noticed the interior lights were on in our new 400 the other night. I waited a while to see if they'd go out, they didn't. I finally figured out the rear hatch wasn't closed completely by the wife when she got home. If they had stayed on all night, I'm sure they would have drained the 12 volt battery which is apparently a real PITA. Guess it's up to us to make SURE all doors are completely closed or risk draining that battery overnight.

[SOMEONE ELSE'S GOT MY NAME]

I noticed the interior lights were on in our new 400 the other night. I waited a while to see if they'd go out, they didn't. I finally figured out the rear hatch wasn't closed completely by the wife when she got home. If they had stayed on all night, I'm sure they would have drained the 12 volt battery which is apparently a real PITA. Guess it's up to us to make SURE all doors are completely closed or risk draining that battery overnight.

Don't all 400h rear hatches lock automaticly? As soon as we begin pulling it down ... it finishes the trip all by itself, if we haven't shut it all the way by hand . . . then, the auto latch can be heard engaging. Perhaps if the auto door open/close function is out of whack, you have an issue ... but otherwise?

[NY_RX400h_Savanah]

I noticed the interior lights were on in our new 400 the other night. I waited a while to see if they'd go out, they didn't. I finally figured out the rear hatch wasn't closed completely by the wife when she got home. If they had stayed on all night, I'm sure they would have drained the 12 volt battery which is apparently a real PITA. Guess it's up to us to make SURE all doors are completely closed or risk draining that battery overnight.

Don't all 400h rear hatches lock automaticly? As soon as we begin pulling it down ... it finishes the trip all by itself, if we haven't shut it all the way by hand . . . then, the auto latch can be heard engaging. Perhaps if the auto door open/close function is out of whack, you have an issue ... but otherwise?

You're right-that happens when switch for interior lights in front and the back are set to "DOOR" position.If the switch is in "ON" position lights will stay on. Also living in the city I park the car in a garage where guys park it-once we had piece of carpet sticking out-so the rear door didn't fully close and lights drained the battery.

[Jim Clark]

I noticed the interior lights were on in our new 400 the other night. I waited a while to see if they'd go out, they didn't. I finally figured out the rear hatch wasn't closed completely by the wife when she got home. If they had stayed on all night, I'm sure they would have drained the 12 volt battery which is apparently a real PITA. Guess it's up to us to make SURE all doors are completely closed or risk draining that battery overnight.

Don't all 400h rear hatches lock automaticly? As soon as we begin pulling it down ... it finishes the trip all by itself, if we haven't shut it all the way by hand . . . then, the auto latch can be heard engaging. Perhaps if the auto door open/close function is out of whack, you have an issue ... but otherwise?

Well, I haven't closed it manually myself, always just push the button, and then I hear/see the automatic system close/lock it. She apparently closed it manually, but not all the way, and the automatic system didn't finish the job. I'll have to verify this can be done but I think it can as she did it.

In any event, it appears we have to be diligent about making sure all the doors are closed all the way.