The TSB from Acura is only days old. So I suggest going back to the dealer to perform the fixes. The prior 3 visits were probably before Acura's fixes were published.
Idle Stop - Randomly Turning off Engine at Stop Lights
I drive a 2019 w/ Tech Pkg with 50K mileage. It comes with Idle Stop. About once a day now, the Idle Stop engages, turns off engine as intended BUT then the Car shifts into Neutral and the engine fully dies. I'm left at stop lights or stop signs with a car that is off and will not restart. I'm so tired of this happening.
My dealership said that Acura acknowledged a similar issue on TLX and pushed a software update to fix Idle Stop. They gave me the Acura complaint phone number (LOL). Coming here to complain first...
Is anyone else having this issue? I'm now searching for a 2018 MDX to avoid any Idle Stop functionality. Yes, I know I can turn it off but I forget, and then have this issue. Very frustrating and not safe. I was almost rear ended today!
My dealership said that Acura acknowledged a similar issue on TLX and pushed a software update to fix Idle Stop. They gave me the Acura complaint phone number (LOL). Coming here to complain first...
Is anyone else having this issue? I'm now searching for a 2018 MDX to avoid any Idle Stop functionality. Yes, I know I can turn it off but I forget, and then have this issue. Very frustrating and not safe. I was almost rear ended today!
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My dealer said this problem has escalated to a full recall and did the software update to out 2019 MDX. We had it not restart on about 5 occasions. It’s very stressful trying to get it restarted in heavy traffic situations.
The software update completely disabled the start stop function. Not sure if that is really a fix for this problem.
The software update completely disabled the start stop function. Not sure if that is really a fix for this problem.
Interesting. I have not been notified of any recall yet. 2019 MDX.
I guess my dealer took advantage of us saying it was a recall.
But after explaining the so called fix, I would recommend not doing this procedure if you want to retain the start stop function!
But after explaining the so called fix, I would recommend not doing this procedure if you want to retain the start stop function!
My assumption is that the startstop software was updated to require much higher battery charge state to ensure it won't stall upon restart. So should stop less, but I'm surprised if it never activates at all. May we worth asking the dealer.
There is a hidden sequence that permanently disables the software. I forget exact steps (google for it) but think if you open the hood with engine running it disables, and if you close the hood with the engine running it renables. Perhaps try closing the hood with your engine running to see if that is a quick fix before going to the dealer.
There is a hidden sequence that permanently disables the software. I forget exact steps (google for it) but think if you open the hood with engine running it disables, and if you close the hood with the engine running it renables. Perhaps try closing the hood with your engine running to see if that is a quick fix before going to the dealer.
That’s what I was thinking but our battery tested over 600 cranking amps. Not so sure if that would be considered low. It’s been over a week driving over 59 miles a day and it never activates, we just get the unavailable message.
next time we’re at the dealer will see if they will warranty the battery.
I’ll try that hood open close trick too.
next time we’re at the dealer will see if they will warranty the battery.
I’ll try that hood open close trick too.
I would take it back to the dealer and ask them to demo idle start/stop functionality on your vehicle.That’s what I was thinking but our battery tested over 600 cranking amps. Not so sure if that would be considered low. It’s been over a week driving over 59 miles a day and it never activates, we just get the unavailable message.
next time we’re at the dealer will see if they will warranty the battery.
I’ll try that hood open close trick too.
Also, I doubt if the vehicle can actually test the battery CCA before triggering idle stop. It must be using just voltage level hence vehicle fails to start if the battery is weak. Since it is a safety hazard, Acura must have totally disabled the feature since it has no way to figure out the condition of the battery.
They claim the battery and starter is now under a 10 year warranty which seems crazy! But they insisted mine is good.I would take it back to the dealer and ask them to demo idle start/stop functionality on your vehicle.
Also, I doubt if the vehicle can actually test the battery CCA before triggering idle stop. It must be using just voltage level hence vehicle fails to start if the battery is weak. Since it is a safety hazard, Acura must have totally disabled the feature since it has no way to figure out the condition of the battery.
If you live in a part of the country where it's cold in winter (I live in MN) you will see a drop in battery charge.
I disable auto idle stop in winter because most of the time it's too cold to turn on and even when it does it's only on for maybe a couple minutes before restarting right away. Just pointless stress on starter and doesn't save any gas.
In summer when it's warm it stays on much longer and can make sense.
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I disable auto idle stop in winter because most of the time it's too cold to turn on and even when it does it's only on for maybe a couple minutes before restarting right away. Just pointless stress on starter and doesn't save any gas.
In summer when it's warm it stays on much longer and can make sense.
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We’re in Florida, so the cold isn’t a factor 😝If you live in a part of the country where it's cold in winter (I live in MN) you will see a drop in battery charge.
I disable auto idle stop in winter because most of the time it's too cold to turn on and even when it does it's only on for maybe a couple minutes before restarting right away. Just pointless stress on starter and doesn't save any gas.
In summer when it's warm it stays on much longer and can make sense.
Sent from my SM-G998U using Tapatalk
I’ve had the software update completed this week. Idle stop has not activated once since. The battery is two years old, purchased from Honda so still under warranty. No issues starting the car from cold.My dealer said this problem has escalated to a full recall and did the software update to out 2019 MDX. We had it not restart on about 5 occasions. It’s very stressful trying to get it restarted in heavy traffic situations.
The software update completely disabled the start stop function. Not sure if that is really a fix for this problem.
I asked about the latest TSB, and they didn’t appear to be familiar with it. I showed them. They said to see how the update worked. Agree that it looks like it’s just disabled it.
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Yup, ours hasn’t engaged once in nearly three weeks. When we do in I am going to ask about this so called fix. Not much of a fix in my opinion!I’ve had the software update completed this week. Idle stop has not activated once since. The battery is two years old, purchased from Honda so still under warranty. No issues starting the car from cold.
I asked about the latest TSB, and they didn’t appear to be familiar with it. I showed them. They said to see how the update worked. Agree that it looks like it’s just disabled it.
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I was experiencing the issue in one of my cars, and they were both recalled for the software update. Hasn't happened since; whether the update actually worked or just coincidence? Who knows.
Update on our MDX, the start stop has not worked once in weeks after the software update. Suddenly it decided to start working again. I have no idea why. We haven’t done anything other than just driving. It’s very odd.
My guess is it learns/calibrates battery drain before and after startup earch morn, and then after it has had time to learn it only stops when it thinks it is safe.
Its crazy how much learning the car does. Transmission learning is frequently documented. But one thing I noticed is that my friction to regen hybrid braking cutover was really harsh after my 3yr fluid flush, and became smooth after about a week as the car must have recalibrated that cutover point.
Its crazy how much learning the car does. Transmission learning is frequently documented. But one thing I noticed is that my friction to regen hybrid braking cutover was really harsh after my 3yr fluid flush, and became smooth after about a week as the car must have recalibrated that cutover point.
My guess is it learns/calibrates battery drain before and after startup earch morn, and then after it has had time to learn it only stops when it thinks it is safe.
Its crazy how much learning the car does. Transmission learning is frequently documented. But one thing I noticed is that my friction to regen hybrid braking cutover was really harsh after my 3yr fluid flush, and became smooth after about a week as the car must have recalibrated that cutover point.
Since the SB work was done, 3-4 weeks ago, idle stop has not worked. I charged the battery to full, tested it and drove 50km. No change. Looks like it was just deactivated and I get reminded of that each time I stop.My guess is it learns/calibrates battery drain before and after startup earch morn, and then after it has had time to learn it only stops when it thinks it is safe.
Its crazy how much learning the car does. Transmission learning is frequently documented. But one thing I noticed is that my friction to regen hybrid braking cutover was really harsh after my 3yr fluid flush, and became smooth after about a week as the car must have recalibrated that cutover point.
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Can someone who has had this update done check to see if the engine still starts back up when you put the transmission into Park? I was reading about the 2019 Pilot, and I guess this feature was programmed into their software. Thanks!
Who here actually got their starter replaced and their valves adjusted because of this?
2019 with 44k miles
Might not be related, but I took my car in for this same issue (going dead at red lights) and they tell me it’s throwing codes that say the transmission needs replacing. (Under warranty thank goodness)
Maybe a coincidence but we will see. Waiting on the transmission to come in.
Might not be related, but I took my car in for this same issue (going dead at red lights) and they tell me it’s throwing codes that say the transmission needs replacing. (Under warranty thank goodness)
Maybe a coincidence but we will see. Waiting on the transmission to come in.
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