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I have a 2018 rlx hybrid with numerous battery, undercharging, brake warnings etc. This car is nothing but headache and I have only 16k miles on it. Sometimes the battery is totally dead in 48 hours. Had battery replaced and spent many days in the dealership. I have to keep a portable jumper handy. At home you would need a trickle charger. Currently, I have brake warning code that the dealer can’t figure out how to fix it and has been in the shop for several day. This is like car in ICU or respirator all the time.
If you drive every day, you probably won’t have problems but I don’t know for certain
I moved your post as it seems your car has some issues to address. I feel for you because my 2014 Sport Hybrid had some weird electrical issues as well, though not as severe as yours. Thankfully your issues seem to be isolated as most of these cars don’t have this kind of issue.
I have a 2018 rlx hybrid with numerous battery, undercharging, brake warnings etc. This car is nothing but headache and I have only 16k miles on it. Sometimes the battery is totally dead in 48 hours. Had battery replaced and spent many days in the dealership. I have to keep a portable jumper handy. At home you would need a trickle charger. Currently, I have brake warning code that the dealer can’t figure out how to fix it and has been in the shop for several day. This is like car in ICU or respirator all the time.
If you drive every day, you probably won’t have problems but I don’t know for certain
Keep us posted on the issue and the fix. I can go several weeks of sitting in the garage without issue with my 18 RLX hybrid. I get the Acuralink low voltage warnings; but, no warning/codes in the RLX screens. Never owned an Acura that absolutely hated low voltage and had all kinds of X-mas light warnings in the dash once I got below 12v (usually low or bad 12v battery, alternator dying, rouge power drain).
Sounds like you may have parasitic drain somewhere that's killing your 12V battery. Do you have any aftermarket radio or alarm installed? You will get bunch of warning dash lights when battery is low or dead. When our MDX was only 2 1/2 years old, I got bunch of Xmas lights on dash after leaving door ajar for awhile. I guess 12V battery was already low, leaving cabin lights on for extended amount of time finally killed it. Fortunately, battery was fully warrantied. Got a replacement 12V battery from dealer, car been good every since. Kind of unnerving to have battery dead on a brand new car after only 2 1/2 years. Modern cars have a kinds of computers that need constant voltage. Any of these systems can malfunction causing battery drain.
Our MDX SH and RLX SH sit in garage for weeks at a time. Never an issue starting them. I do put them on trickle charger if we don't drive for extended period.
I am glad to hear that your RLX doesn’t have issues. There are no after market parts or anything added to it. The dealer just called and said it is a under voltage issue but they cannot replace any parts unless there diagnostic codes tells them to. Acura will not reimburse them without computer diagnosis. I opened up a call with Acura customer relationship and I understand the dealer’s dilemma. It is unfortunate that they do not have the ability to look at the schematics of the charging system and take various readings along points to determine exactly where the under voltage is coming from. They rely on their diagnostic code to tell which component should be replaced. Thank you for the advice and I will keep posted.
PS they cleared the error code several times but it comes right back.
My wife also has an '18 RLX Sport Hybrid. It's got about 10k on the odometer, but has been driven only about 2k miles in the last 10 months due to her retirement :-). The car sits for at a minimum 5 days between driving. So far the only issue we've had is the "nag-o-gram" email from AcuraLink when it detects the battery below a threshold such that you can't do remote things via the app, but when you go to the car itself it's fully functional and no starting or voltage issues at all (this email comes if you let it sit for a week or more). So (knock on wood) I haven't seen any sort of parasitic battery drain on her car like you describe. Just another data point...
Battery issues are not unique to the RLX during the pandemic as ANY CAR that is not being driven at least 30 minutes twice a week is going to need a trickle charger to properly maintain the battery. Sadly, modern cars are designed to be used and the plethora of electronic gadgets all require a tiny bit of power that adds up to drain the battery when they sit for long periods of time. Compounding this fact is the innate weakness of lead/acid batteries that lose capacity when they are severely discharged, so once you have let your battery "die", it will never have 100% capacity again. If it "dies" more than a couple of times, it is time for a replacement regardless of how old it is.
I went through the same thing as the OP when I first got my 2014 RLX Sport Hybrid because it had sat on the lot or in the showroom for a long time, the battery had died and been recharged many times and simply didn't hold a full charge. The battery was replaced and I had no trouble whatsoever UNTIL the pandemic came around and my car sat for long periods without being driven (I was only driving it once a week maximum and sometimes for short trips). A few months ago I had Acura install a new battery and I invested in a good trickle charger and I have had no problems since.
Note: the trickle charger that I bought (Noco Genius 10 (I'm up in Canada, so I'm not sure if it is available in the U.S.)) claims that it can detect and repair sulfation and acid stratification thus "repairing" batteries that have been weakened by repeated deep discharge. I have no idea if this works if a battery has been severely weakened, but if you need a trickle charger anyway, it might be worth getting one with this feature and trying to "repair" your existing battery.
I agree with @hondamore . Sounds like it’s time to invest in a trickle charger. I have to use one on my NSX because as low-tech as it is, battery drain is a thing.
I have a 2018 rlx hybrid with numerous battery, undercharging, brake warnings etc. This car is nothing but headache and I have only 16k miles on it. Sometimes the battery is totally dead in 48 hours. Had battery replaced and spent many days in the dealership. I have to keep a portable jumper handy. At home you would need a trickle charger. Currently, I have brake warning code that the dealer can’t figure out how to fix it and has been in the shop for several day. This is like car in ICU or respirator all the time.
If you drive every day, you probably won’t have problems but I don’t know for certain
Which battery are you referring to? 12v in the engine bay or high voltage batter in the trunk? I don't know how often you drive your RLX, but if it's the high voltage, perhaps it was not driven in a while? But if it's 12v, something's not right as there is some drainage going on.
Presuming the new battery is good, one possible 'next step' is the battery sensor located at the 12v battery terminal. I have heard of charging issues and system faults if this item has problems.
See if you can check the manufacture date on that 'new' battery. If more than 2 years ago, it is no longer 'new', particularly if it has a deep discharge history.
For my used 2019 SH with 2k miles, one of the first things i did was get a new AGM 12v. This was to fend off battery problems caused by likely deep discharge on this used car previous to purchase.
I agree with @hondamore . Sounds like it’s time to invest in a trickle charger. I have to use one on my NSX because as low-tech as it is, battery drain is a thing.
how does the hybrid system work? Looking to buy a rlx sport hybrid. Does it require charging? and if so, if u could please explain how it works would be helpful.
The hybrid battery pack is recharge with the 3.5L engine and/or regenerative braking. You can't recharge the hybrid battery pack manually. You can only recharge the 12v car battery manually. The only way that comes close to a manual recharge is to put the RLX hybrid into "Sport" mode and the 3.5L engine will charge the EV battery pack 100% ASAP to provide maximum power from the 3.5L V-6+3 electric motors. In normal mode, the hybrid battery pack will charge between 1/3 to 3/4 range with the RLX deciding when to go in/out of electric vehicle mode, V-6 only, or a combo of both using all 4 motors with sh-awd. The most you have to do is put gas in the tank and the system takes care of the rest. The downside of the RLX hybrid is the 15 gal gas tank, rear seats don't fold, and much smaller trunk because of the battery pack.
If we are talking about the regular battery & not the hybrid-related one: I went thru a period where mine was dying after only a few weeks. We discovered that I was storing the key fob too close to the vehicle and that was draining the battery. Once I started keeping the fob far away from the vehicle, the problem never resurfaced.
Lucky for me I have a good relationship with the dealer and they gave me 2 new batteries free of charge as we investigated the issue.
TSX69 . . . Are you saying the batteries would not have been covered had you not been chummy with shop? Assuming this would have fallen under the not covered by warranty collection area they like to plop things into they don’t want to pony up for. Unless the manual specifically says to keep the fobs away from the car, how could they claim negligence? Just asking a question out loud.
Glad it worked out for you and glad to have the keep fobs at a distance tip!
They would have replaced the batteries that only lasted a few weeks as that was just plain weird.
I do not remember how old the battery was the 1st time I brought it in but if I understand battery warranties correctly, they prorate the cost of the existing dead one as a discount off of the new one. For instance, if you have a 4 year warranty & then it dies after 2 years, you get 50% off the replacement. I think ... ? They just gave me a new one free.
Now that I think about it, it is strange that the RLX did not have that issue from the beginning. I am pretty sure it started around my 2nd or 3rd year of ownership.
My co-worker bought a new VW Taos over the weekend but when she got up yesterday morning to go to work, she discovered the battery was dead. It had to be towed to the dealer and was not ready by end of the day so she is still waiting to hear what is wrong with it.
i’ve been making the same joke about that new VW EV. im like you’re going to buy an electric anything from VW?! I am however anxious to see what Honda will come up with.
I really hope Acura doesn't take the under-powered EV route like so many others. I willing to pay more to get more; but, not the other extreme in the +$100,000 range. Only paying $1500 for my MDX hybrid over a sh-awd MDX Adv was worth is for me. I still think we are 15-20 years away from having the battery tech and quick charge infrastructure to have an EV tipping point. Hybrids and Sport hybrids are the perfect missing link until we do.
I hope you are wrong mrgold35. Fifteen to twenty years seems like a long time to perfect something already in the works. But with the two steps forward, one step back approach to fuel burning alternatives, who knows what will happen over the next ten to twenty. In the meantime, i’ll continue to wait and watch to see what Acura and Honda does.
If we are talking about the regular battery & not the hybrid-related one: I went thru a period where mine was dying after only a few weeks. We discovered that I was storing the key fob too close to the vehicle and that was draining the battery. Once I started keeping the fob far away from the vehicle, the problem never resurfaced.
Lucky for me I have a good relationship with the dealer and they gave me 2 new batteries free of charge as we investigated the issue.
Nice tip. I am already keeping my keys in a Faraday cage-type key holder. Works quite well to keep the car from communicating with the fob. Dunno if it’s strong enough to keep a determined thief from reading the key fob code into my car, but it does keep me from accidentally opening the trunk while at home.
My wife has killed a battery while on the other side of town, and had an issue a couple of other times. Christmas tree lights on the dash being the big indicator.
She likes to forget her fob in the cup holder overnight.
Another tip I just learned by searching online is: when 12V battery is nearing its end of life, telescopic steering wheel movement will "not work" until 12V battery is replaced.
The reason I searched for this was today's 12V battery that I think gave up on me. The car was sitting for the last week, and it appears the 12V battery is either stock or was replaced by the previous owner - anyhow, I jumped it and took it to the dealer to swap the 12V battery and clear out any lights.
Next time, about 2 years from now, I will test the battery and when replacement is nearing, I will get a better cc-power battery from the local parts store vs the OEM battery... it seems it is only 550 cold cranking rating...
I already had to replace my OEM battery on my 18 RLX hybrid back in Dec 2021 under warranty with 18,600 miles. I was getting an U0104-00 ACC may not work properly with baking system and U1100 Gauge control module loss of communication errors. The errors haven't returned with new OEM 12v battery replacement. I've never gone over 3 1/2 years with Acura OEM batteries in all 5 of my current or previous Acuras living in the southwest. I'm right at 3 years and 4 months with the original battery on my 19 MDX hybrid.
I have a 2016 RLX Sport Hybrid with 70,000 miles. I am the original owner. It's a fantastic car, super reliable with exceptional drive-ability and performance. I agree with most of the observations above.
My long term fuel economy is 27.5 MPG. I drive smoothly, not hard on the pedal, but I drive fast out here in big sky Arizona. In seven years I've had two non-maintenance repairs: I replaced the steering wheel tower adjustment motor that was scratching and making a grinding noise; and I replaced the engine compartment hood struts that were losing their stay-open power after seven years. Both repairs were covered under 7/100 AcuraCare so I ended up paying about the same for the warranty (from Curry Acura online, great company) as the repair would have cost me. The noise in the steering column actually started before the 4/50 warranty expired but I did not notice it enough to care about it under our trusted service manager told us it was a thing and recommended we replace the steering column. I believe later models won't have this problem. The engine compartment struts, I just was looking for something before the warranty expired but they needed replacing.
The driving experience is superb. We also have a 2023 MDX-S and I understand the MDX and the RLX-SH are different vehicles but wow ...... the RLX make me wish the MDX Type S was a 400HP Sport Hybrid.
I'd buy another RLX-SH in a second, and would not sell mine now. I drive it to work every day and plan to drive it for at least ten years. The only thing I'd change is CarPlay and probably one day I'll install the aftermarket upgrade (...could someone please remind me about what this is?). I wish the audio system bass was a little boom-ier .... the seats and the stereo in the MDX-S are better than the RLX, but I don't miss this stuff as much as CarPlay.
Pic below is my RLX at seven years and running strong!
Last insight >> listen to NeutronBob, he knows things.
Last edited by Scott in AZ; 01-31-2024 at 10:23 PM.
My dream MDX is the 3.0L turbo Type-S with the Sport Hybrid powertrain for +425 hp/tq. Second choice would be the 310hp 3.5L from the RLX+Sport Hybrid system in the Type-S MDX. I will stick with my 19 MDX Sport Hybrid and 18 RLX Sport Hybrid until then.
My dream MDX is the 3.0L turbo Type-S with the Sport Hybrid powertrain for +425 hp/tq. Second choice would be the 310hp 3.5L from the RLX+Sport Hybrid system in the Type-S MDX. I will stick with my 19 MDX Sport Hybrid and 18 RLX Sport Hybrid until then.
RLX-SH is 377+ HP, not 310. Torque is instantaneous. 5-second zero-to-sixty is very controllable with AWD. Or maybe you mean just the ICE with no Hybrid?
RLX-SH is 377+ HP, not 310. Torque is instantaneous. 5-second zero-to-sixty is very controllable with AWD. Or maybe you mean just the ICE with no Hybrid?
The 14-20 RLX 3.5L has 310hp/273tq and you add in the 67hp/68tq from the hybrid system to get the 377hp/341tq. I would take a MDX Type-S with the RLX 3.5L 310hp/273 3.5L+hybrid powertrain for the same 377hp/341tq NOT the the MDX 290hp/267tq 3.5L+64hp/71tq hybrid powertrain for 354hp/338tq for my second choice dream MDX Type-S if I can't get the 355hp 3.0T.
I just wish Acura would have used the 290hp or 310 hp 3.5L NA V-6 instead of the 257hp 3.0L NA V-6 for the 17-20 MDX Sport Hybrid AND made this powertrain an option for the 4th Gen MDX.
RLX-SH is 377+ HP, not 310. Torque is instantaneous. 5-second zero-to-sixty is very controllable with AWD. Or maybe you mean just the ICE with no Hybrid?
While the torque is great and far better than most similar types of car/powertrain, it is not instantaneous. Only EVs will have such torque available from standing still.
Regarding the AWD, I'd agree, that 0-60mph in 5 sec or faster is pretty solid and planted... I would add to your comment that RLX "sh-awd" is not the same and not as great as traditional SH-AWD - specifically, in moist road areas, RLX SH is likely to have little bit of slipping, where RL SH-AWD I had under the same conditions would not (same tires, same condition, same speed, same curved road, etc.)... don't get me wrong, SH-AWD is still great, but just not the same.
The only thing I'd change is CarPlay and probably one day I'll install the aftermarket upgrade (...could someone please remind me about what this is?). I wish the audio system bass was a little boom-ier .... the seats and the stereo in the MDX-S are better than the RLX, but I don't miss this stuff as much as CarPlay.
You are referring to GROM VLine2? I have had that installed in my 2020 RLX-SH for about 3 years now. Rock solid. It has gotten frequent updates thru the years now Wireless Android Auto/Apple CarPlay works great. Start the car, wait about 15-20 secs for GROM to boot up and automatically connect to my phone to launch wireless AA. Usually by the time I pull car of my garage, AA is launched and ready to go. If you need more details check out my post under Audio section. I love the delay power-off feature. Lets say you're running an errand to FedEx store. You stopped and turn off the car, run into FedEX and back into your car with 15 minutes, start the car, GROM will still be running and resume your navigation and music where you last left off. It's very convenient.
Beautiful RLX Scott. I like your wheels a lot better than mine (2020). Stunning backdrop. Arizona has some really beautiful scenery. I did grad school at Thunderbird a long time back. Only time I ever lived out west. My favorite drive ever was from Thunderbird in Glendale to my friends parents home in Park City Utah. Coming from Queens NY I never experienced that type and level of natural beauty and driving pleasure (even in a stripped down most basic VW Golf stick).
[QUOTE= My favorite drive ever was from Thunderbird in Glendale to my friends parents home in Park City Utah. Coming from Queens NY I never experienced that type and level of natural beauty and driving pleasure (even in a stripped down most basic VW Golf stick).[/QUOTE]
Highway 89 and 93 in a VW manual transmission? I made same drive from Idaho Falls to Phoenix in 1989 in an '88 GLI. Everybody should make that drive once! Happy trails!
While the torque is great and far better than most similar types of car/powertrain, it is not instantaneous. Only EVs will have such torque available from standing still.
Regarding the AWD, I'd agree, that 0-60mph in 5 sec or faster is pretty solid and planted... I would add to your comment that RLX "sh-awd" is not the same and not as great as traditional SH-AWD - specifically, in moist road areas, RLX SH is likely to have little bit of slipping, where RL SH-AWD I had under the same conditions would not (same tires, same condition, same speed, same curved road, etc.)... don't get me wrong, SH-AWD is still great, but just not the same.
yes the RLX slipping bothers me sometimes. I still need to get used to it
02-27-2021, 12:14 PM
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On a Semi-Related Note
