Shada

12v battery problem hopefully

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Been having issues with the 300h for two days. Wife said first day when she got into car to leave work the car wouldn't go, message on the dash saying hybrid system stopped put shift lever in park even though it was in park! Some lights flashing on dash and something beeping!

switched off for 10 minits try again and away it goes. 

Day 2. Starts in morning no problem, evening go to leave work, same problems only this time it wouldn't power off again either. Eventually it did shut off and again 10 minits later it went perfect.

i can't get the car to replicate the fault but I suspect the 12v Battery has had it! Anyone experienced anything similar?

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Hi Shada, you are right it will be the 12v Battery I had the same issue when I had my is300h I had the Battery changed under warranty by Lexus 

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It does seem to me that there's a problem with the IS300h 12v Battery. I had a replacement under warranty for a 3 year old Battery and yet my experience with other/ previous cars is that the Battery lasts around 10 years nowadays. My Jag. Xj8 Battery was 15 years old when I traded in the car and had never, ever, needed any attention and that was with an annual mileage of only 3,000 so it didn't get much charging. My Lexus quiescent discharge has been measured by the dealer at 16 mA .... well below the max. permitted figure of 30 mA and the Battery shows 14.0 to 14.3 volts when the car is switched on so there's nothing wrong with the charging system but the Battery voltage falls to 11.5 to 11.7 after being left unused for 3 days. This is sufficient to start the hybrid system but seems peculiarly low for a 12 volt AGM Battery.

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when my Battery went flat due to the car not being used i had the same issue

with the dashboard with the lights flashing, needles flicking & the park message

so yes change the Battery.

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This problem is common across the complete Toyota/Lexus range of hybrid cars. If the Battery voltage level falls below 10.6 volts while the car systems are booting the various ECU's see the wrong voltage response from numerous sensor, and in turn see's this as faults with these systems.

The reason the Battery drops to this voltage is because  one of the first things that operates is the hydraulic brake pressure pump "this can be set off just by opening the drivers door". This pump uses initially 40 amps, and climbing as the pressure load on the pump increases dropping the Battery voltage just as the computers are booting.

Leaving the car turned off for a few minutes then trying again allows the Battery to recover somewhat, and since the hydraulics are still up to pressure the pump does not run to load the Battery.

John.

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Interesting that, about the brake booster pump. I'll listen for it next time I get in the car.

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The brake booster makes sense. That's the part I'd left out in the equations In my head! I've not seen the car act up. I've replaced the 12v Battery now and on holiday for a few days. Will see how it goes when I'm back. 

Both days there was high heat and also heavy rain. Been changing quite a few car batteries getting killed with heat this past few weeks so hopefully this is the end of problems. 

New bosch Battery with 4 years warranty for anyone interested out of warranty and looking options other than dealer. 

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Just had a service mot and hybrid health check which failed with a P3000 error code. Have googled the above and there will be further numbers to identify the problem further. The dealer told me to run the car for about 300 miles and they will test it again. Not sure if this is to clear any fault codes or to charge the 12v Battery. I have just fully charged the Battery using my ctek charger just to make sure. Could this be the 12v Battery failing, it is 6 years old now.

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6 minutes ago, Bob99 said:

Just had a service mot and hybrid health check which failed with a P3000 error code. Have googled the above and there will be further numbers to identify the problem further. The dealer told me to run the car for about 300 miles and they will test it again. Not sure if this is to clear any fault codes or to charge the 12v battery. I have just fully charged the battery using my ctek charger just to make sure. Could this be the 12v battery failing, it is 6 years old now.

Hi Bob, Sorry to read your news.

Please tell me exactly, when was your previous Hybrid Health Check and how many miles have you covered since then ?

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Hi john, last one was 12 months ago and covered about 8000 miles,

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you have to drive the 300 miles as all Battery condition code has been erased,

during the 300 miles new codes are created and stored and from these

codes the condition of the Battery can be evaluated.

 

 

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23 minutes ago, Bob99 said:

Hi john, last one was 12 months ago and covered about 8000 miles,

If you mean less than 365.25 days then it was under warranty !!!

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Yes it's less than 12months will see what codes they find in the next few weeks. Thank you both for your responses. 

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5 minutes ago, Bob99 said:

Yes it's less than 12months will see what codes they find in the next few weeks. Thank you both for your responses. 

Remember, it should be under Warranty !!

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Update on hybrid issue. Car has gone back for another hybrid health check which it again failed. Error code is P3000/388. I was asked if I had left it in neutral or run out of fuel both answers were no. This code leads to control problem or Battery problem. They have kept the car and will run it for a further 300 miles, not sure that will help. Been left with a 69 plate RC300h so it will be nice to see the difference. Think they are struggling at the moment unless they can swap the Battery pack and test again.

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P3000-388

Discharge Inhibition Control Malfunction. This code is triggered when the battery’s state of charge decreases due to the vehicle being left in N position, running low on fuel or a malfunction occurring in the HV control system.

Possible causes include: HV control system, HV Battery assembly or a fuel shortage

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Thanks Phil, read that before on google need to know what the diagnostics are for the control system now.

 

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Car brought back today took 400 miles and a few restarts to recalibrate the system. This allowed the hybrid test to be completed satisfactorily. All good now, had really good service from preston lexus.

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21 minutes ago, Bob99 said:

Car brought back today took 400 miles and a few restarts to recalibrate the system. This allowed the hybrid test to be completed satisfactorily. All good now, had really good service from preston lexus.

Glad it's worked out in the end and great to know that, as I'm in Preston, that I'll be able to go there and get good service.

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31 minutes ago, Bob99 said:

Car brought back today took 400 miles and a few restarts to recalibrate the system. This allowed the hybrid test to be completed satisfactorily. All good now, had really good service from preston lexus.

All dealt with under warranty Bob ?

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Yes John, apart from the petrol I put in for the original 300 miles of journeys I didn't necessarily need to do. It was on a quarter of a tank when they picked it up for the second test and was on three quarters when brought back, fully valeted again. New certificate for the year and 10000 miles. I am now thinking of scenarios that could have triggerd the fault. The car was stopping and starting as it should and the Battery was charging ok. 

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7 minutes ago, Bob99 said:

Yes John, apart from the petrol I put in for the original 300 miles of journeys I didn't necessarily need to do. It was on a quarter of a tank when they picked it up for the second test and was on three quarters when brought back, fully valeted again. New certificate for the year and 10000 miles. I am now thinking of scenarios that could have triggerd the fault. The car was stopping and starting as it should and the battery was charging ok. 

Great news and wonderful service too Bob.Thanks.

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My late -65 IS300h went in for its 4 year service last week and came back with a note on the Hybrid Health Check that the auxiliary Battery shows signs of deterioration and that I should contact my Service Advisor. I did this but the only advice that I received was to use the car more. Apparently during the HHC the auxiliary Battery voltage dropped to a level where warning beeps were emitted. This is with a replacement Battery supplied last November. I have taken to monitoring that Battery voltage at the time of switching on just to see how long the car can be left and the voltage so far is never less than 11.5 which is sufficient although remarkably low for a 12 v AGM Battery. Anyway I received an email from Lexus HQ asking my opinion regarding the service and so I took the opportunity to spell out the history a bit with the underlying question that I've never before owned a car that required such regular use in order to keep it in a startable condition ( think 2 week holiday with car left in airport car park). My suggestion to Lexus is that the Battery is under specified for its task. I await developments.

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23 minutes ago, reeac said:

so I took the opportunity to spell out the history a bit with the underlying question that I've never before owned a car that required such regular use in order to keep it in a startable condition ( think 2 week holiday with car left in airport car park). My suggestion to Lexus is that the battery is under specified for its task. I await developments.

I doubt you'll get anywhere with that, but good on you for trying.

It's a matter of economics I expect. A hybrid car requires very little current to get it going (just over 15A for my RX450h as opposed to over 300A for a traditional starter motor) so they don't have to put a big Battery in and can save loads of money. Lexus, quite rightly in my humble opinion, will assume that people buy cars to use them rather than having them parked up for long periods of time.

If you're worried about getting a flat Battery and your car lives in the open as opposed to being garaged, you may want to buy a solar panel trickle charger like this one here for example.

If that's not viable due to the car being garaged, maybe a jump start Battery pack is more appropriate, like this one here.

Of course, all this begs one underlying question (and not just to you personally but to anyone who doesn't use their car on a regular basis) - why would you even buy a hybrid car in the first place? The whole ethos behind a hybrid is built around batteries and we all know that any and every Battery will self-discharge over time and has to be kept topped up, so why buy a car that needs regular use to just leave it sitting around?

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I own the car as a convenient implement to use when I need to, not when I have to to keep it in running condition. I've owned cars built in 1932, 1949, 1956, 1958, 1958, 1964, 1973, 1978, 1985, 1986, 1990, 1996, 1998, 2005 and 2015 and the last one is the only one which has been this needy. Battery lives have improved over the years and I now find average 10 years or so except for the Lexus. Just to clarify, I own 3 cars... a 1958 MGA which I restored and put on the road in1983, a 2005 Honda Jazz which I bought new and the 2015 Lexus. We're both retired so no commuting mileage, the MG is just for pleasure in the summer months (and retains its Battery charge for months), the Jazz is for rough use such as transporting mucky stuff, towing a trailer etc and the Lexus is mainly for longer trips. Sounds pretty extravagant but we're not hard up. I'm very pleased with all aspects of the Lexus except for this auxiliary Battery business. which I feel could easily be fixed. 

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  • Club Hybrid Poll

  • 71 Hybrid Reliability

    1. 1. If you were to consider buying a Hybrid model over 5 years old, would you be worried about the reliability of the Hybrid system?


      • Not really as Hybrid systems are always reliable
      • Not if it had a Manufacturers Warranty on the Hybrid system
      • I would not buy a Hybrid model over 5 years old