2014+ Jeep Cherokee Forums banner

No power after reattaching negative terminal

19K views 23 replies 13 participants last post by  phatgreatwall 
#1 ·
2016 Jeep Cherokee 3.2L Latitude

My wife came home the other day and she said the radio is stuck on a bluetooth call. I tried truning off the car and restarting the car. After different attempts and different ways I disconnected the negative terminal to try to clear the radio. I reattached the negative terminal. When I tried starting the car there was nothing. No crank. No start. No dashboard lights.

Did I blow a fuse? or fry something?

Any help would be appreciated.
 
#2 · (Edited)
Hi there and welcome to the forum !

Wow sorry to hear that. First time I hear of such an issue, to be honest.

I have disconnected my battery, once, to install an HID headlight kit, and I noticed the Positive terminal was a type I hadn't come across before and kinda difficult to tighen up. But the Negative terminal, from what I recall, was mostly straightforward to re-attach and tighen.

A couple questions :
1) When you turn the key to ACC or ON (or press the button if you have keyless), do you get anything like dome lights, or any sign of electricity running ?
2) Have you checked battery voltage, if you have a multimeter ?

If you have zero power and battery voltage is good, and battery terminals are tight, we'll need to look for something like a fuseable link or master fuse somewhere...
 
#4 ·
Next time just restart the uconnect system by pushing in the mute/pause button and the other big dail button to the right for about 8 seconds.

Sent from my ONEPLUS A3000 using Tapatalk
 
  • Like
Reactions: Rand and Duke2015
#5 ·
FYI. The radio has its own internal battery. This is why you can disconnect the negative terminal on the battery and not lose any of your presets or settings! I have no idea how long it takes to run down the battery in the radio, but I once had my radio out for 4 or 5 hours and did not lose any of the presets and settings. The above mentioned restart/reset would be the way to go.
 
#6 · (Edited)
FYI. The radio has its own internal battery. This is why you can disconnect the negative terminal on the battery and not lose any of your presets or settings!
Do you KNOW that the radio has its own internal battery, or did you deduce it from not losing your settings? Because you wouldn't need power just to keep your settings. I don't think most modern devices rely on RAM for data storage anymore. All you would need is a small storage device (such as an internal flash memory device) for that info to be written to, and it could be read each time uConnect boots up. I don't know how this radio in particular works, just talking theoretically here.

https://en.m.wikipedia.org/wiki/Non-volatile_memory


2014 Cherokee Latitude AD1
 
#9 ·
Not absolutely positive. Wonder if clock has to be reset on head units without GPS. If yes, that would suggest no battery or storage capacitor.
 
#11 ·
Whenever you reset the system (using the push-both-buttons method), the clock resets to 12:00. Fine with me, because I have to set the clock monthly, as it loses about 5 minutes every month.
 
#16 ·
One of the hazzards on doing a battery disconnect to solve an issue or as I would say a forced reboot.
Vast majority of times nothing bad happens but the chance is always there.
The same goes for a PC. Pull that plug and you are rolling the dice to do that forced reset.
Just my humble opinion
 
  • Like
Reactions: dhh3
#22 ·
With my Windows 10 on a Dell All-in-One, if I walk away from the computer, eventually the screen saver comes on. From this point, I hit the Enter Key (Any Key will work) and the computer is ready to go; like it never went to sleep. The screen saver will stay on for hours, sometimes for days. Other times (I've never timed this because I have never witnessed this) the screen saver goes off, screen is blank and the computer is really sleeping. At this point, I have to hit the power button on the side of the computer, and log back in. I get the home page, but it takes a few minutes to do anything; I hear the HD turning and clicking, so it must be trying to wake up from a deep sleep. Windows 7 in my old computer never did this.
 
#23 · (Edited)
Ah yes... the complex sleep and hibernate states of Windows, and which triggers wake it up.
There are multiple settings for Power Management. You can pretty much set what sleeps or hibernates and when, and for how long. You can also choose what hardware can wake the computer (network card, mouse, etc..). Sometimes though you have tasks running in the background that can and will delay sleep/hibernate.

I believe Microsoft has improved power management in recent systems, in a way many people now just let the computer sleep instead of shutting it down when the computing day is over. Laptops are a perfect example : I see many people just close the lid and throw it in the bag, which leaves it to hibernate (per settings, but hibernate will happen with most default power settings). This allows a quick wake and people like that.

I much prefer a traditional shutdown, to get a fresh session at next boot. In my case, I use FireFox and always leave like 15 tabs open all the time, and FireFox is known to abuse RAM, so shutting everything down helps keep memory usage *normal*. But that's me, haha.
Edit to add : I don't need hibernate to get quick bootups, because I use SSDs only now ;)
 
  • Like
Reactions: dhh3
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top