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Remote start not working when cold

I've been dealing with the same issues with my 2020 rebel back in January first they told me I wasn't driving it enough. Then they decided to replace the alternator that didn't work. Then they tried to tell me it was frozen def.. all these times they had to recharge my battery from 51%. When spring came the problem disappeared. Now that the weather is turned cold again I've had it back in three times for three complimentary battery charges. And they keep telling me it's not the battery. Now it's a software update. With another complimentary battery charge. Next week is supposed to be cold so we'll see how long it takes to call them again
I’m starting to wonder if the truck uses the intelligent battery monitor sensor along with ambient temp to change the rate of charge or level of charge depending on temperatures. I know some battery chargers do this, so it’s possible the truck is programmed the same way.

I’m also expecting colder weather again mid week so we’ll see if this second software update changed anything.

I’ve driven my truck just over 60000km in 19 months of ownership, if an average of over 100km or 60miles driven per day isn’t enough to charge the battery up then we need a better/bigger alternator along with programming to allow a faster charge rate.
 
Anyone have the remote start issue when it's really cold, solved? It has gotten cold again and again my truck won't remote start after sitting overnight. I am thinking about getting a battery warmer for it. Has anyone else tried one?
 
We’ll, my remote start has failed to function 3 days already this month but the truck starts just fine if you get in and start it. Even from 3 feet away all I get is on flash of the lights and I can hear the fuel pump kick on but that’s it, no attempt to engage the starter.

This morning I was also greeted to a black and then blue screen when I put my truck into reverse, I’ve had this truck just under two years and have never had that before.

I already had the tab update performed last year When my remote start wasn’t working, but I’ve always felt my battery was weak which I believe was caused by it going completely dead multiple times when the truck was new due to a bad ground. Going to push for a new battery, hopefully it tests bad. Truck is driven daily.
New battery won't cure the problem. I pushed and had my battery replaced even though it tested good. The problem is when it gets cold the battery loses a lot of capacity and when it tries to start the computer senses that the battery voltage is low and won't allow it to start with the remote.
 
I've been dealing with the same issues with my 2020 rebel back in January first they told me I wasn't driving it enough. Then they decided to replace the alternator that didn't work. Then they tried to tell me it was frozen def.. all these times they had to recharge my battery from 51%. When spring came the problem disappeared. Now that the weather is turned cold again I've had it back in three times for three complimentary battery charges. And they keep telling me it's not the battery. Now it's a software update. With another complimentary battery charge. Next week is supposed to be cold so we'll see how long it takes to call them again
Same story for me since last winter, new battery and all. So far the bcm update solved my issues. So far....
 
Anyone have the remote start issue when it's really cold, solved? It has gotten cold again and again my truck won't remote start after sitting overnight. I am thinking about getting a battery warmer for it. Has anyone else tried one?
Get the bcm update first...
 
Anyone have the remote start issue when it's really cold, solved? It has gotten cold again and again my truck won't remote start after sitting overnight. I am thinking about getting a battery warmer for it. Has anyone else tried one?
I honestly wouldn't bother with a battery warmer. While we all had the same issue of the remote start not working in the cold it seems different solutions worked for different people. Going to an AGM H8 battery has worked for me so far (knock on wood). It's been in the -30's here for the last few weeks and I haven't had one failed remote start which is a record for me. The longest my truck sat unused is 3 days and it fired right up with the app. I generally use my truck every day but with the extreme cold plus covid it's hard to get motivated to go somewhere on days off. If I ever do get another failed remote start I will ask my dealer to do a BCM update but for now I'm trying to avoid them.
 
Just an update to my situation. Got my truck back Thursday and they said it was a software update. Complimentary battery charge again. And they wanted me to put some miles on it. Where are you going to go on a holiday weekend? Anyways this morning I go to hit the remote start and voila it's not working again only took 3 days to get back to the same state. Last night was 20° here so it was cold enough to make something happen. This is getting really frustrating
 
I honestly wouldn't bother with a battery warmer. While we all had the same issue of the remote start not working in the cold it seems different solutions worked for different people. Going to an AGM H8 battery has worked for me so far (knock on wood). It's been in the -30's here for the last few weeks and I haven't had one failed remote start which is a record for me. The longest my truck sat unused is 3 days and it fired right up with the app. I generally use my truck every day but with the extreme cold plus covid it's hard to get motivated to go somewhere on days off. If I ever do get another failed remote start I will ask my dealer to do a BCM update but for now I'm trying to avoid them.
I do have a newer AGM H8 battery with the battery blanket on my 2020 Ram 1500 with the Ecodiesel..... Well, I went out and bought a battery warmer. I installed the battery warmer, connected it to a timer for it to turn on at 3:30am and to turn off at 6:30am. At 6:15am I attempted to start my truck with the remote start and it started right up. it was -14°C this morning and the problem usually shows up when the temperature gets to about -7° and below. The problem is when it's cold the battery loses capacity and when it loses capacity the voltage drops, when the truck receives the remote command to start the computer sees this reduced voltage, thinks the battery is dead and terminates the remote start. Only way to rectify this problem would be to have the people who write the programs for the ECU lower the threshold for battery voltage.
 
It surprised me this morning when my truck remote started fine at -8C. Maybe the update it working, time will tell.

On a side note my mileage sure drops when I get to spoil myself with a warm cab and heated seat and steering wheel.
 
1F here last night and it worked okay for me. We'll see if that holds true in February lol.
 
It surprised me this morning when my truck remote started fine at -8C. Maybe the update it working, time will tell.

On a side note my mileage sure drops when I get to spoil myself with a warm cab and heated seat and steering wheel.
Do you happen to know the update number?
 
So you're telling me it's normal for my battery to drop to 54% capacity in 3 days after receiving a full charge and driving every day? That doesn't seem right to me but I don't know. When I talk to the service manager he told me my truck threw a code for the def pump. They thought that might have been the problem. But like I said in 3 days I had the same problem again. So I dropped it off last night they checked it this morning the remote start failed when they check the battery it was down to 54%. So they considered the battery fail. So now I have a new battery. I guess we'll see how long it takes to act up again. The code they were seeing was P20FB-00. And that's what they flashed my PCM for. Which they hoped would work but didn't work in the end
 
So you're telling me it's normal for my battery to drop to 54% capacity in 3 days after receiving a full charge and driving every day? That doesn't seem right to me but I don't know. When I talk to the service manager he told me my truck threw a code for the def pump. They thought that might have been the problem. But like I said in 3 days I had the same problem again. So I dropped it off last night they checked it this morning the remote start failed when they check the battery it was down to 54%. So they considered the battery fail. So now I have a new battery. I guess we'll see how long it takes to act up again. The code they were seeing was P20FB-00. And that's what they flashed my PCM for. Which they hoped would work but didn't work in the end
I wouldn't expect a battery to drop by that much. What was the temperature? "lead-acid batteries drop in capacity by about 20 percent in normal to freezing weather, and down to about 50 percent in temperatures that reach about -22 degrees Fahrenheit".
 
Well, it was 0ºF or -18ºC this morning. The battery warmer is working great as my truck was able to remote start for the 3rd morning in a row when the temperature was 7ºF (-14ºC) or below.
 
Well, it was 0ºF or -18ºC this morning. The battery warmer is working great as my truck was able to remote start for the 3rd morning in a row when the temperature was 7ºF (-14ºC) or below.
-8C here today and my remote start worked, colder temps coming Monday and Tuesday tho. Wish I knew the bcm software version that was installed so I could provide it to others with the same issue.
 
-8C here today and my remote start worked, colder temps coming Monday and Tuesday tho. Wish I knew the bcm software version that was installed so I could provide it to others with the same issue.
My truck wouldn't start when it was approx 20ºF (-7ºC) or below. It also wouldn't start if the truck sat for 4 days with temperatures near freezing. You are right on the threshold of where it didn't work for me. You'll find out for sure when it gets colder. Hopefully the BCM update cured yours as it has been frustrating.
 
I wouldn't expect a battery to drop by that much. What was the temperature? "lead-acid batteries drop in capacity by about 20 percent in normal to freezing weather, and down to about 50 percent in temperatures that reach about -22 degrees Fahrenheit".
It's been between 20 to 34 degrees F...so not extremely cold yet...new battery now so no issues for a little bit anyway...
 
It's been between 20 to 34 degrees F...so not extremely cold yet...new battery now so no issues for a little bit anyway...
Hopefully it works out for you as a new battery didn't solve my problem.
 

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