Register a free account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members through your own private inbox!
The RF Hub most definitely makes the determination before releasing information to the BCM to proceed with starting the engine. It’s on the list of bussed inputs and outputs for the RF Hub module.
If the RF hub makes this determination, wouldn't it be a simple fix as all they would have to do is upgrade the firmware with new parameters for the remote start? From the looks of it, this problem has been happening for a while.
Sure it would. But the question is, is the determined voltage threshold for a remote start event requested that way from engineering for a specific reason?
I see discussions of this very problem going back to at least 2014.
Definitely. It could happen to any model year FCA vehicle, and when it does happen, people are going to complain about it on forums. It just seems to be way more prevalent across all ram forums with the 5th gen 1500s and 2019+ HDs. But, was it determined to be a problem with the remote start system as it’s designed to not remote start under a certain battery voltage, or a problem with the battery losing too much voltage in cold weather.
I think there are other issues going on, such as parasitic loss or the battery not being sufficiently charged. There is no reason a battery voltage should be so low at above 0°F temperatures. . Unfortunately I'm not going to be able to test if the battery is sufficiently charged by charging it externally till fully charged and then letting it sit in the truck overnight as the temperatures aren't going to be anywhere near as cold as it was. I'm leaning towards battery not being sufficiently charged as the voltage varies anywhere between 12.7 and 14.6V while driving.
Do you have an eco diesel? Is this fluctuation only happening about the first 10 minutes of driving after a cold start? Keep in mind the glow plugs will continue to cycle on and off when the engine is running, and that’s a huge current draw when they do cycle.
Yup
This is happening after 10 minutes and the current draw shouldn't be so much to drag the battery voltage down to 12.5V that I noticed today as the truck has a 250A alternator which is more than enough current to power everything the truck can throw at it and be able to charge the battery at the same time.
it even says in the manual that you do not have to lock it first.it does it on its own.
Glow plugs on the eco diesel, and the grid heater on the CTD will EASILY pull voltage down 2 volts when they are cycling on and off. The length of time this happens varies based on temperature. This behavior with the voltage fluctuation is described in the owner’s manual.
It’s definitely a RESULT of the way the RF Hub is programmed. The problem is- is it an actual ISSUE in FCA’s eyes, being that they may have intentionally wanted the threshold set that way. It’ll be a hard one to have them update if that’s the case.
Was this for me? If so, I changed my stock battery to an Odyssey 94R AGM battery over a week ago. Unfortunately, the very next day the truck wouldn't remote start either. I have been checking and I do have an intermittent parasitic drain. Sometimes I check and I have nothing (20mA) sometimes I have over 1.5 amps. One time pulling F38 eliminated the draw but that was a one-time thing. Between the remote start issues and the weird voodoo that I experienced this morning from my previous post, I also suffer from the "chirping going over bumps issue" and there's a thread on that topic and lot of people are affected. I don't expect to be the owner of this truck by next winter (even though I love it despite the issues!).Really weird. If you hadn't already just been through this routine, I'd say check the battery...
All this talk about batteries did get me curious about mine. I work from home right now, and Friday the dogs stayed home, so I didn't drive it. I have a heated garage that is currently set to 50. It sat Friday, Saturday, and Sunday. Sunday night, I checked the battery with my battery tester: 410 CCA.
Monday, after taking the doggos to daycare (roughly 20 minutes there and 20 minutes back), I tested it again, and it said 721 CCA. (Its the regular battery, not AGM, so 730 CCA rated.)
So I wonder how low it would get if I let it sit for a 5 days or a week, say on a trip out of town... guess we'll see.
No worries, it's my bad I misread your first sentence but I get it now!
The only time I've ever had the horn honk and the flashers go while I'm in the car is if I accidentally hit the panic button. Is there a chance it accidentally got pushed while it was in your pocket?
No sir, my fob was sitting in my backpack on the backseat the whole time and it happened a second time roughly 5 minutes later. I tried to manually turn off the flashers but all that did was change the flashing frequency. This was pure voodoo!
