Update:
Battery unchargeable, return car to dealer for service and battery changeout.

 

Sorry to hear about your problem. I am documenting battery drain problems on my T8 here: T8 stopped working
http://forums.swedespeed.com/showthread.php?t=304009

My car is currently with the dealer while they try to reproduce the problems I've been having. No cause has yet been identified.

Hope yours is a simpler diagnosis.

 

Thanks ntt,
Looks to me as if several cells in the 12v battery have shorted, so at this time
I believe it's just a faulty battery. Voc is towing to the dealer tomorrow.

Jumping the battery revives electrical systems in my case (so long as jump present)
So hopefully can get car out of garage and on to flatbed.
In cases of completely dead electrical system, how does volvo expect one to be able to put
car in neutral and deactivate the
air suspension as required per the manual?
Some cars have switches to disable air system in such cases.

Will post update soon.

 

Dead starting battery on T8 ..and T6

XC90 is dead! Had to use mechanical key to get into the car. Could only open the four passenger doors, tailgate has no mechanical release, so I could not get my charger out of the storage compartment (with the spare tire) because of limited clearance and access to the "start battery". Volvo manual describes the two batteries (start battery and support battery) et on pages 503-507.

Bought another charger and after 4 hours at 8 amps the battery charge indicated that the "battery" was charged and in trickle charge mode. The manual states that when charging the start battery the support battery is also charged. Makes sense as they are most likely in parallel. However, I can be easily confused as the the instructions in the manual are to charge the battery from the engine compartment - where the support battery is for the "Start/Stop" function.

Even though the battery charger states the battery is fully charged and no longer drawing current the XC 90 is dead. No response from remote key of any form: door lock/unlock, engine start, accessory mode, unlocking and raising the tailgate by being in range but using the mechanical grip above the license plate.

Made this trip for an important medical appointment on Monday. car dies on Saturday, no support on Sunday, and probably loss of car for three days (1 for towinng, 1 for servicing and 1 for just schedule). I knew there would be software/technical geekish problems, but for such an expensive car I really expected the reliability and availability to be better.

 

Sorry to hear about your problems. I remember the anguish when my T8 died on the weekend. I've updated my thread with more information on how my car was fixed. It ended up being the tailgate foot sensor waking up due to radio signals in my neighborhood! So these issues can be tricky. I hope you get a quick resolution to your problem. Volvo was very helpful with mine.

 

Just returned to my 2017 XC90 T8 and also found its battery completely dead. Have any other UK owners experienced similar starter battery issues?

 

I saw a thread on the UK forums... MANY have. Me included, although I am not in the UK.
After reading and given my own experience with two different XC90s (a 2016 D5 and a 2017 T8), I have come to the conclusion that, if your car is idle for two weeks, it will probably start. Three weeks, it's a crapshoot. Four weeks, it won't. It just won't.

 

My T8 sat for over 3 weeks and it started just fine. Of course I ALWAYS lock my car as a precaution every single day for FWIW. I think Locking it great reduces the risks.

 

Locking puts most systems in sleep drawing minimal power whereas unlocked it remains in standby ready to engage Sensus and other systems for when the door is opened. If leaving it idle for long periods of time it is advised to keep it locked to avoid excessive 12v battery drain.

 

I have a 10 month old XC90 T8 and have had 3 problems. I had a turtle show up on the dash display and it would only allow the car to go 10mph luckily I found a outside outlet and charged the car for 45 minutes and then it was ok.
I go to the airport on monday about 5 am at the parking lot and come back on friday late or saturday early morning and the car starts ok then drive home for 1hour and leave the car sit all day saturday and try to start it on sunday and the battery voltage is 4.7 volts. This has happened 2 times. The foot switch for the rear hatch was replaced but didn't solve the problem. I dropped the car off today and measured the battery at the dealer after a 30 minute trip and the voltage was only 12.0 volts. They are not going to start it till monday and then check the voltage drop but then they will still have to try to figure out why it is drawing more current.

 

The battery on my T8 was bad. It would smell while charging the car (the starting battery also charges at the same time). The battery had a bad cell. It's crazy that with all that juice in the regular battery, there isn't some type of "jump start mode" where the car can be powered from that.

 

Yeah. Very few hybrids actually have this ability. Not sure why they even need the 12v batteries except to fit in with the rest of the vehicle's electronics.

 

Just returned from a two week trip and encountered the same problem. Do you guys recommend calling Volvo corporate or the dealership with this issue? The complimentary on call just expired.

 

My dead T8 Battery

I left the T8 with 50% battery, and left on a 7 week trip. Came back to a dead car. Without any juice left, the car wouldn't take the charging cable.

Without power, I couldn't open the rear hatch (where the battery was) or the glove box (where the manual was). I use the manual on my App instead.

I jump started the car with the +/- posts under the hood, with power now available from the 2nd vehicle, I put the T8 into Start.

Next I put the car into Power Mode and enabled "Charge", since Power Mode means the engine runs non-stop. I left the vehicle running like this for an hour and see the battery up to 1/4+. Turned off the vehicle to make sure I can start the car again. Thinking I was good, I dropped off my kids and when I came out after 5 minutes it was a dead car again, not even power available to the door locks.

I jump started the car again and drove home in Power Mode. When I shutoff the vehicle I left the door open to ensure the vehicle didn't go to sleep mode (lights + chime both on), and plugged in the Charging cable. It accepted the charging cable, I think this is key.

After that, the vehicle got fully charged and everything is now back to normal. When it was charging, I did notice the time to Fully Charge got extended during this process (quite a bit more than the normal 15 min jump), so the computer must have calculated the inital power available incorrectly.

In retrospective, if this happens again, I would just put the car to Start, and activate "Charge", since this would start the engine. I don't think putting the car in Power Mode would have made a difference in terms of charging the battery.

That's a lot of power drain on these T8's when not used. I hope Volvo can improve the power management so that people can at the very least start their car. The Hybrid battery can be drained, but the 12V in the back should not be dead after a few weeks of sitting.

 

I left the T8 with 50% battery, and left on a 7 week trip. Came back to a dead car. Without any juice left, the car wouldn't take the charging cable.

Without power, I couldn't open the rear hatch (where the battery was) or the glove box (where the manual was). I use the manual on my App instead.

I jump started the car with the +/- posts under the hood, with power now available from the 2nd vehicle, I put the T8 into Start.

Next I put the car into Power Mode and enabled "Charge", since Power Mode means the engine runs non-stop. I left the vehicle running like this for an hour and see the battery up to 1/4+. Turned off the vehicle to make sure I can start the car again. Thinking I was good, I dropped off my kids and when I came out after 5 minutes it was a dead car again, not even power available to the door locks.

I jump started the car again and drove home in Power Mode. When I shutoff the vehicle I left the door open to ensure the vehicle didn't go to sleep mode (lights + chime both on), and plugged in the Charging cable. It accepted the charging cable, I think this is key.

After that, the vehicle got fully charged and everything is now back to normal. When it was charging, I did notice the time to Fully Charge got extended during this process (quite a bit more than the normal 15 jump), so the computer must have calculated the inital power available incorrectly.

In retrospective, if this happens again, I would just put the car to Start, and activate "Charge", since this would start the engine. I don't think putting the car in Power Mode would have made a difference in terms of charging the battery.

That's a lot of power drain on these T8's when not used. I hope Volvo can improve the power management so that people can at the very least start their car. The Hybrid battery can be drained, but the 12V in the back should not be dead after a few weeks of sitting.

what year is your XC90 T8?

 

The hybrid battery should not be drained as it is just used to charge the 12v battery and its capacity is so big.

The 12v battery could be drained somehow due to unexpected drain and they should fix it.

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That's interesting... But I had nothing in the hybrid when the car was jump started. Are the hybrid and 12v connected while locked? And Hybrid would charge the 12V while locked?

 

New to the forum (and to Volvos), but I have a follow-up question regarding the T8. I frequently use a trickle charger on my BMW X5d (all the electronics on a modern SUV can eat up battery power at an alarming rate). Would this be useful for the "starter" battery on the T8? Would it mess with the main Li-Ion battery? Does the main charging cable also charge the starter battery? BMW dealerships usually have every one of their showroom cars on a trickle charger just to keep the battery charged up; not needed on the T8? Looking forward to thoughts from the experts here....

 

I remember reading in the owners manual that when you've got the charging cable plugged in, it also charges the starter battery.

 

That's correct and when driven the LiOn will maintain the 12V (T8 doesn't have a traditional alternator).

 

Follow up question then, if the car is left unplugged for a period and then before discharge plugged in will it restore the 12v starter? I ask because I often take long trips and we will have access to a part time charger while I'm away but wouldn't be able to "hog" the plug the entire time.

I'm thinking airport parking valet type scenarios which offer to charge your car before you come home. If I'm away 3+ weeks it might just squeak under the dead 12v timing

 

Yes - although keep in mind, the Hybrid battery is the one that is actually used to start the ICE, not the 12v battery since the T8 doesn't have a traditional starter. The 12v only exists in the T8 for purposes of powering accessories (legacy 12v system). I wonder now since it's not required to be a starter battery if it's a Deep Cycle instead - would be really cool and make sense.

From my manual pg 512 (varies depending on edition/version):

Start battery
The vehicle's electrical system is single pole and uses the body and engine block as conductors.
The start (main) battery is used to power electri- cal components and systems. However, the hybrid battery is used to start the gasoline engine.
The start battery should only be replaced by a trained and qualified Volvo service technician.
The start battery is an Absorbed Glass Mat (AGM) 12-volt battery that is dimensioned for use in vehicles to support electrical systems and functions.
The service life of a battery is affected by factors such as driving conditions/style, the number of starts, climate, etc. Extreme cold may also further decrease the battery's starting capacity.
• Never disconnect the start battery while the engine is running.
• Check that the start battery is correctly con- nected and that the clamps on its terminals are properly tightened.

 

My guess here is that at 25% certain features are killed from getting the parasitic draw. Like your phone going into "low power mode" when at 20% battery.

A smarter move would be to put a feature into Sensus that says, "Long Term Parking Mode" and have it only leave absolutely essential features powered.

 

My guess here is that at 25% certain features are killed from getting the parasitic draw. Like your phone going into "low power mode" when at 20% battery.

Storing Lithium Ion batteries at 40% charge prolongs their life. My guess is that Volvo recommends 25% because they keep a 15% reserve to always be able to engage rear wheel drive when needed.

I say that because the 2017 T8s have a 9.2kWh battery, but a full charge never takes above 7.8kWh, which means about 1.4kWh is always kept in reserve.

A smarter move would be to put a feature into Sensus that says, "Long Term Parking Mode" and have it only leave absolutely essential features powered.

The T8s are smart enough to put themselves in battery save mode when we don't drive for a few days. I have been out of the country for the last 2+ weeks while the car has been in our garage. When I launch the VOC app, it tells me that the car is in battery save mode.

The car won't be driven for another 4 weeks. I hope it starts up and runs fine when I get back home. Before this, the longest I have gone without driving is about 2.5 weeks, twice, and I didn't have any trouble.

 

I have a dead vehicle now too. Door seems to have not been closed after getting something out of the car. Can I reasonable expect to just plug the car into the charger to make it start working again. Right now as it stands nothing works at all including the trunk and displays and the locks


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I have a dead vehicle now too. Door seems to have not been closed after getting something out of the car. Can I reasonable expect to just plug the car into the charger to make it start working again. Right now as it stands nothing works at all including the trunk and displays and the locks

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I don't think so, based on my prior experience - or, well, experiences (plural).

You will need, at least, to jump-start. Whether the starter battery will need replacement or not is a crap-shoot.

 

Let me get this straight. If I leave my XC90 T8 at the airport for a month, which I’ve done with multiple vehicles over the years, I’ll come back to a dead car with no access to the rear battery to jump start it? IE There is no manual way to open the rear hatch door once the 12V battery dies? Did I get that right? Seems like a major fail here on Volvo’s part.

 

Let me get this straight. If I leave my XC90 T8 at the airport for a month, which I've done with multiple vehicles over the years, I'll come back to a dead car with no access to the rear battery to jump start it? IE There is no manual way to open the rear hatch door once the 12V battery dies? Did I get that right? Seems like a major fail here on Volvo's part.

Yes, you'll likely come back to a dead car. At least, I did multiple times - and the dealership confirms that is "normal" and "expected." Of course, I think that's nonsense...

But I don't understand the second half of your question. Perhaps because I have very little mechanical skill/knowledge. You do not need the rear hatch door to jump start the car - the starter battery is up front. You need the physical key (opening the FoB ranges from trivial to impossible, depending on when it was produced, but that is a whole different thread...).

 

Stevey - for some reason, the forum won't let me reply directly to your post. Go figure.

Is it covered under warranty? Yes.

For as much as the situation irks me, I have to admit Volvo has always been quick at sending someone to jump start the car - even at late night hours, I waited less than 20 min. The starter battery replacements and software updates were all free, quick, and they even came to pick up my car at home after it was jump-started (to replace the starter battery, just in case) and left me with a loaner.

The bad news is that none of this has helped.

The dealership has recommended disconnecting the battery (it is even in the manual, somewhere were discussing long-term storage), or using one of those external chargers. I have not followed their advice. It's easier to call them, wait 20 min, and let them deal with the issue. But your equation may vary. My dealership is right next to the airport, where my car usually dies

 

Is anyone aware of the size of the starting battery? This has happened to me twice after a weeklong trip now. I would like to upgarde to an Odyssey AGM.

 

I would like to upgarde to an Odyssey AGM.

The OEM battery is AGM. Replacing the battery without addressing the cause of the parasitic current draw will continue to kill batteries.

 

The problem that everyone is identifying as a design issue is pretty common for Hybrid vehicles and in general most all vehicles. I had a Prius 2005 and 2006, as well as a Highlander Hybrid 2015. All three would suffer from a dead battery if left for an extended time. While locked there is a thief system as well as the smart key system that monitor the surroundings. So naturally, the battery is going to drain if left long enough. Fortunately if that happens you can still get inside by pulling our your hard key. Our Kia Soul EV+, Nissan Leaf, as well as our Chevy Bolt EV all came with hard keys that were built into the smart key. So you can gain access into the car. From there you can open the hood and attach a charger. You might be able to save the battery, though if it was allowed to go without a charge for too long a period, a cell or two can be damaged. Our XC90 has the same capability. There is a key built into the smart key that allows access to the car via the driver's door. That is the only door I believe allows for a hard key. The solution is don't leave your car without some means of trickle charging for excessive amounts of time. It is a no brainer. Most car people get it. So don't blame Volvo, as no one has a car that will survive for extended periods of time consistently without some sort of trickle charge. It is all about chemistry, and getting worked up won't change that. Some of the older cars had very little in terms of electronics that sucked the juice out of the battery. Still batteries are not perfectly isolated devices and will discharge over time. Even lithium will hold for only a certain period of time. You can buy lithium 12 volt automotive batteries but they are in the many hundreds of dollars. To save weight I used one in my supercharged NSX. But I had to have a special trickle charger that worked the cells in a very specific manner otherwise the battery would be toast. You can try and disconnect the terminals from the battery both front and back and that will give you a bit more time. That will help with parasitic consumption. Otherwise take an Uber and keep your car at home on a trickle charger.

 

I found the answer on page 507 of the 2017 manual, it is a H8 AGM group size, or:

13.9" x 6.9" x 7.5" (353x175x190mm)

lamar, right, the proper solution is to find the parasitic draw, though I believe it actually isn't a "parasitic draw" at all, but a draw that is happening as designed - in this case maybe the lift gate sensor as mentioned in anotherthread.

drmanny3, I also have a 2012 Lexus RX450h and it has never required a jump start, so unfortunately I do think this is a design flaw by Volvo. In this case the car only sat for 6 days.

Odyssey's PC1350 is rated for 88.5-95 Ah which is the same as the OEM battery (95 Ah, as stated in the manual), so lamarguy is right. I guess the best solution is to ask them to disable to lift gate sensor, or whatever else might be drawing power.

SDSpeed, I love the Odyssey on my 2005 Subaru Legacy GT. I use it in conjuction with my QuickJack and it holds up much better than Optima's I've bought - but then again I also learned to run the car while using the QuickJack and bought a NoCo G7200 trickle charger. The lithium jump starter is a good idea, I have one I keep on hand for my parking business. I just wish there were a simpler solution because the XC90 is actually for my mother. I'm more than happy to pop the hood myself but would wish a lower-involvement experience for her, especially since I steered her towards the car.

 

I believe it actually isn't a "parasitic draw" at all, but a draw that is happening as designed - in this case maybe the lift gate sensor as mentioned in anotherthread.

It may be the tailgate sensor, but I'd try to work with the dealer before replacing another battery. There may be a software fix they can apply.

If you're DIY, hook up an inline multimeter/ammeter (20 amp) to the negative terminal to check the current draw after the ignition is OFF and the doors are locked. The current draw should be < 1 amp. You could then test pulling the tailgate sensor fuse to get a definitive answer.

 

I had left car in garage from Sept. 24 to Nov. 11. I could start my T8 with no issues. I had the same issue in 2016 and it was towed two times. Seems like software upgrade helped.


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Dodgy starter battery inT8

Hi everyone. Owned xc90T8 for 3 years with no problems apart from starter battery losing charge causing engine to come on all the time and warning lights. Can only charge to 10.5v so does this mean battery is dead?

 

2020 V60 Polestar starter battery died WHILE CAR PLUGGED IN.

I left the car plugged into 110V AC for three days, and at the end of the three days the car was unresponsive. I measured the 12V system voltage to be 3V.
I attached another 12V battery to the charging points under the hood, which allowed me to unlock the car. The extra 12V battery brought the internal battery to 10V in a few minutes. To get the internal battery up to 12V I disconnected the external battery and started the gas engine, POLESTAR MODE, and drove for several minutes. The car warned of a Hybrid System error. [Remind me to edit this with the exact error message.]
After that drive, I measured the internal battery at 12.3V. It's been around that for the past 18 hours. I want to take it to a dealer, but I read horrible reviews on most of the dealers near me, especially the one I can walk back home from. I bought the car six weeks ago, and it was manufactured in November 2019. It was the show car for the DC auto show, which may explain why the accessories battery would be in bad shape, although COME ON!
Most people in this thread are talking about the 12V battery losing energy while parked unplugged. Mine was plugged in.
To add a bit of mystery: I had noticed a weird plastic part in the back of the car where the jack is stored. Yesterday, during the ordeal, I realized that it was the cover for the positive terminal of the 12V battery. Thus I realized that the dealer probably had the same problem, having to charge the battery the day they sold it to me-Now I think I know why it took them so long in the shop to prep it for me.

 

I left the car plugged into 110V AC for three days, and at the end of the three days the car was unresponsive. I measured the 12V system voltage to be 3V.
I attached another 12V battery to the charging points under the hood, which allowed me to unlock the car. The extra 12V battery brought the internal battery to 10V in a few minutes. To get the internal battery up to 12V I disconnected the external battery and started the gas engine, POLESTAR MODE, and drove for several minutes. The car warned of a Hybrid System error. [Remind me to edit this with the exact error message.]
After that drive, I measured the internal battery at 12.3V. It's been around that for the past 18 hours. I want to take it to a dealer, but I read horrible reviews on most of the dealers near me, especially the one I can walk back home from. I bought the car six weeks ago, and it was manufactured in November 2019. It was the show car for the DC auto show, which may explain why the accessories battery would be in bad shape, although COME ON!
Most people in this thread are talking about the 12V battery losing energy while parked unplugged. Mine was plugged in.
To add a bit of mystery: I had noticed a weird plastic part in the back of the car where the jack is stored. Yesterday, during the ordeal, I realized that it was the cover for the positive terminal of the 12V battery. Thus I realized that the dealer probably had the same problem, having to charge the battery the day they sold it to me-Now I think I know why it took them so long in the shop to prep it for me.

Shawn, we recently had a spate of battery problems with our XC90 2020 T8. The car would be non-responsive after just 1-2 days despite being plugged in and charging the whole time. At first the dealer applied a software update that sounded like a similar issue; that didn't fix it. Then the dealer took the car for a few days, keeping it charged on their fancy Volvo charging systems and couldn't reproduce it. Finally when it still happened, they escalated to Volvo USA who did some kind of remote monitoring and connected it using the factory cable on a 120v outlet and were able to reproduce the problem. They eventually diagnosed it as a faulty charging unit of some sort (I don't have the exact part in front of me). After that the issue has been fixed - despite a month of nearly no driving we have had no issues since getting it back from the dealer. So you might ask the dealer to have Volvo USA monitor it, but be prepared for 3-4 days without the car (if you even want to deal with this in the current situation.). Good luck! We were at our wits end with the car and the process - I feel your frustration! (Also FWIW, we had good luck with Volvo On Call folks coming quickly and starting the car, and got some satisfaction of this costing Volvo something every time we got the car. We also insisted on loaner vehicles from the dealer which seemed to motivate them to do something about fixing our issue.)