Ok, I just recently experienced some karma with my remote start after previously stating in this thread that I had no issues yet (go figure). I had a 2014 Ram 1500 sport for over 6 years and never experienced any issues whatsoever with the remote start. The truck was traded in with the original battery still going strong.
I use the Uconnect app to remote start when I'm at work as the truck is far away and I can't see it and I usually use the keyfob when I'm home cause I can hear the truck start but on occasion I use the app at home. My issues with the remote start on my 2020 Rebel started about 2 weeks ago. At the end of my shift one day I opened the app and gave it the start command. A minute later I received the "Remote start failed" message. I tried again and same thing. I started walking toward my truck and when it came in sight I used the keyfob and it remote started no problem. I thought that was rather weird. For the next several days I never had any issues remote starting with the app or fob. Actually, at this point in time I never had a remote start fail with the fob so I started to think maybe it was a software issue with the app until recently.
Temperatures really took a dive here over the weekend. On Saturday morning it was in the -40's (celcius). I went outside and plugged in my truck and my wife's van. About 5 hours later I attempted to remote start the truck via the app when I was in the garage. I could hear the horn beep once and I received the message that the truck started (when it didn't). Weird. I than attempted to start with the keyfob and same thing (one horn honk and no start). I than went out and started manually. The truck started fine (no sign of struggle). After about 10 minutes I went out and about (groceries and stuff) and kept the truck running the whole while I was out. When I came home I let the truck sit for a few hours (plugged in) and attempted the same process as before (app followed by fob) with the exact same results as before.
Grabbed my multimeter this time and low and behold: 11.66 volts. Odd thing the truck manually starts with no issues at all even at that voltage. That's where I'm at right now. It was too cold to do any further troubleshooting and it's Monday so I'm back to work. Luckily I carpool with someone and they offered to drive all week. This is driving me crazy though. We spend all this money on these trucks only to have certain features not being reliable. Remote start is pretty much mandatory where I live! I plan on digging into this further this weekend. Right now it's looking like my battery is causing the issue. I plan to check the battery current when the vehicle is off in case I have excess draw. One thing I won't be doing is taking the truck to my local dealer. I'll update this thread when I get some more info this coming weekend.
The attached image below is from the Challenger forum. I thought it was rather odd as they state that remote start battery range is between 11-15 volts. First I heard of it. I was always under the impression that a normal battery voltage is around 12.6 volts. 12.4 is acceptable but anything under 12v was an indicator of a bad battery. Maybe someone out there can shed some light. Did batteries change that much over the last few years and I'm out of the loop?
Sorry for the long post I wanted to include as much significant information as possible.
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