When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I just replaced the battery on my 2015 C7. Pretty easy except for the cramped space. HOWEVER, now that it is hooked up I have lights and flashers, but no dash screen, no infotainment screen, no ignition; I can hear the door opener click when I press the button but the doors won't open, except by the manual emergency release. The window go up and down. What am I missing?
A few thoughts:
- verify that battery cable clamps are pushed down flat and level, then tightened
- a new battery is not always a good battery - should be at least 12 volts
- some things work, others don't so battery is not dead
- did you get a spark when disconnecting or reconnecting battery cables?
- there are several distribution fuses on top of the positive battery terminal that feed the fuse panels - one may be blown
- use a volt meter or 12 v test light to check these fuses
- if battery voltage and fuses OK - disconnect negative battery cable for 30 min and reconnect - this forces a cold boot of all computer modules
See pic below of distribution fuses on the battery:
The volt meter shows over 12 V from the battery. A test light indicates power to all of the terminals on the + side and to the 2 wires connected to the plate at "3" and "4" .
I have just pulled the ground and will wait until later this afternoon to see if I can reboot the systems after a couple of hours of dormancy.
Last edited by psollitto; Sep 25, 2020 at 12:33 PM.
Ron,
Thanks for staying with me on this!
Where do I check to get on the other side of that fuse? I would assume it will be the post with the nut right below "350 A", looking at your posted picture.
Can I tell if the fuse has been tripped by looking at it?
If tripped, can it be reset or is it replaced?
Last edited by psollitto; Sep 25, 2020 at 03:05 PM.
No problem. Troubleshooting is kind of fun. It always helps to have a second set of eyes. Look at the pic above. There is a stud / nut where the red cable attaches. The stud on the bottom side of the fuse is where this replacement fuse is attached to the buss plate. Check from red cable stud to a ground or negative battery terminal.
I got tied up with work yesterday and was unable to continue with this issue until this morning.
Rebooting did not help, but I did find that was not getting any power to the large red wire connected to the post on the far side of the 35A fuse. I was getting power to the post on the near side (closer to the + battery terminal) and all the other posts . The plate under the large red wire on the far side (after the fuse) had power; so the fuse is good. BUT the post itself and the exposed metal on the red wire had no power. After looking closely at the large red wire I realized that when tightened it cocked about 2 degrees to the rear. I loosened the nut and held the wire perfectly in line and tightened it again. This time it went about an extra turn or two and I NOW HAVE POWER TO THE LARGE RED WIRE!!!
Apparently there is a little "nub' on the outside (to the rear) of the plastic housing that was keeping the wire's metal tab from making a contact.
Thanks to RonC7 for helping me through this!!!
Last edited by psollitto; Sep 26, 2020 at 10:04 AM.
OP - Just saw your update after I wrote the post below. Glad it is resolved! (I didn't take any individual wires loose when I replaced the battery in my 2014).
Congratulations! You appear to have blown the 350 amp fuse. That's the bad news.
Good news! You are not the first. You can either buy the whole fuse assembly that sits on top of the positive battery terminal, or just the 350 amp fuse.
Take pictures of everything / label wires before you take anything apart.
It appears that the fuse replacement solution is to bend the 350 amp fuse back and forth to break it off from the buss, drill a hole, and bolt the replacement 350 amp fuse into place on the buss, then reassemble. The new fuse has shiny copper lugs.
Battery help
