C2101 & C2103 codes

KCsJKU

KCsJKU

Member
Joined
Jan 2, 2020
Messages
41
Location
Atlanta, GA
Any help would be great. I have a 2014 JKU and was driving this evening when all the sudden, I had an audible tone (like low fuel), my speedo went to 0 and slowly went back to the speed I was going and my traction control light came on. About 5 minutes later, it did it again. I noticed just a slight loss of power for a second when this happened. It happened a3rd time and now the battery light was on too. When I got home (this all happened within a 10-12 minute time frame), I began to back into my driveway and it dies. I try to crank it again and nothing. Had to take it out of gear and roll it down the street. A few minutes later, I was able to crank it and I read the codes. It showed C2101 and C2103 for battery and system high voltage. My traction control light is off now and no codes for it. Anyone have similar issues?
 
I had an identical issue, literally.

Mine turned out to be the brake light switch, which is on the pedal assemble right on top of the brake pedal lever arm. Apparently it was getting stuck (replacing it fixed this) and causing these errors, as well as a loss of power, traction control light, etc. Scared me the first time it happened because I was on the highway and suddenly lost speed and all throttle, then it went right back on.
 
  • Like
Reactions: KCsJKU
I forgot to come back and update. Everything I read, which there wasn't much out there in regards to these codes, was a loose negative battery terminal. I double checked and sure enough, my negative terminal was loose, but was as tight as I could get it. So I replaced my terminal with a brass terminal and was able to tighten it down. I cleared the codes and so far, we haven't had a repeat of the issues. It's not a DD so I haven't gotten that many miles on it since replacing, but hopefully that fixed it. I had the battery replaced 6 months ago and didnt notice any issues with the terminal then.
 
  • Like
Reactions: BigAL07, BLACKJKU and Chris
Sounds like you may have solved the issue. Hopefully that was indeed the fix, and if it was, it just goes to show that sometimes the simplest explanation is the right one. Let us know how it holds up, and thanks for the update!
 
  • Like
Reactions: Daddyo2373, BigAL07 and KCsJKU
Chris said:
I had an identical issue, literally.

Mine turned out to be the brake light switch, which is on the pedal assemble right on top of the brake pedal lever arm. Apparently it was getting stuck (replacing it fixed this) and causing these errors, as well as a loss of power, traction control light, etc. Scared me the first time it happened because I was on the highway and suddenly lost speed and all throttle, then it went right back on.
Click to expand...

I’m having the exact same problem and the dealer pretty much told me to kick rocks because I have an aftermarket radio and other things connected to the battery. I want to sell my JK so I can stick to my TJ full time so I want to get this fixed. Do you know any other things this might be? It seems like it could be the ecm (I hope not), brake light switch, possibly camshaft position sensor?
 
Mine turned out to be a loose negative battery terminal. It was slightly loose but I couldn't tighten it any further. Replaced my negative terminal with a universal terminal and was able to tighten it nice and snug. Haven't had an issue since (knock on wood).
 
Andresme said:
I’m having the exact same problem and the dealer pretty much told me to kick rocks because I have an aftermarket radio and other things connected to the battery. I want to sell my JK so I can stick to my TJ full time so I want to get this fixed. Do you know any other things this might be? It seems like it could be the ecm (I hope not), brake light switch, possibly camshaft position sensor?
Click to expand...

You know, it's really, really tough I've found to diagnose the JKs because they are so electronic. My TJ on the other hand is pretty damn easy to figure out due to being much simpler (much less electronics).

I can't say for sure, but it might be worth taking to an independent Jeep mechanic.
 
  • Like
Reactions: Daddyo2373
I have the same issue. Was driving down the highway at 105kms. All of sudden both speed and rpm meters fell down and there was a beep sound and traction light turned on for a sec. Jeep was literally switched off even cruze control broken and than turned on within 3 sec and dashboard lighted up the way we turn the key and car starts. It is recurring frequently sometimes and sometimes it rubs just fine do not know whats the matter.
 
Please correct your profile Jash. We spell it Canada or CANADA here, not CaNada. All Good. Happy Thanksgiving again US of A.
 
I mistakenly used a capital letter thought it will diappear whn the final profile will come up but it stayed as it is and I dont know how to edit it now so...
 
You go to the top right and get into your account details. There you can make changes and then press save. I am always changing my Avatar. Why you may ask? Because I am fortunate to have nothing else better to do.
 
  • Haha
  • Like
Reactions: Jashanmaan5077, mrjp and Chris
Andresme said:
I’m having the exact same problem and the dealer pretty much told me to kick rocks because I have an aftermarket radio and other things connected to the battery. I want to sell my JK so I can stick to my TJ full time so I want to get this fixed. Do you know any other things this might be? It seems like it could be the ecm (I hope not), brake light switch, possibly camshaft position sensor?
Click to expand...
 
Andresme said:
I’m having the exact same problem and the dealer pretty much told me to kick rocks because I have an aftermarket radio and other things connected to the battery. I want to sell my JK so I can stick to my TJ full time so I want to get this fixed. Do you know any other things this might be? It seems like it could be the ecm (I hope not), brake light switch, possibly camshaft position sensor?
Click to expand...
It could be the ABS Speed sensor, my front passenger needs replacing. My JEEP keeps throwing the ABS on every now and then when I brake at low speeds. I did replace my battery a few months ago so I will be checking if that might be why the brake/abs/traction light has been coming on randomly. I might have not tightened it correctly. Since I have a manual transmission I haven't been getting the speed to go down, but I do sense a loss of power which has been affecting my Bluetooth Uconnect connection.

2015 Wrangler Unlimited Sport S
 
Chris said:
I had an identical issue, literally.

Mine turned out to be the brake light switch, which is on the pedal assemble right on top of the brake pedal lever arm. Apparently it was getting stuck (replacing it fixed this) and causing these errors, as well as a loss of power, traction control light, etc. Scared me the first time it happened because I was on the highway and suddenly lost speed and all throttle, then it went right back on.
Click to expand...
Yep, I had all the same issues and my obd read a bad brake switch. Changes it out in about 15 minutes and so far no more problems. One quick thing though, after you changed the switch make sure you pull back on the brake (toward you) before you run a new set of diagnostics. I didn’t and had a whole slew of errors I won’t go into and my Jeep wouldn’t move. Since you have to push a little forward on the brake pedal to install the new switch it holds the brake on and thus the errors and not moving.
 
  • Like
Reactions: Chris and mrjp
Iflyu2 said:
Yep, I had all the same issues and my obd read a bad brake switch. Changes it out in about 15 minutes and so far no more problems. One quick thing though, after you changed the switch make sure you pull back on the brake (toward you) before you run a new set of diagnostics. I didn’t and had a whole slew of errors I won’t go into and my Jeep wouldn’t move. Since you have to push a little forward on the brake pedal to install the new switch it holds the brake on and thus the errors and not moving.
Click to expand...
How do I remove and re-install the switch. I need to insert a brake light kill switch because the jeep is towed.
 
Last edited by a moderator:
I had the same issue on 2016 JK. Made changes as mentioned here. I added a post him, it is now tight, and I changed out the switch. We will see if this works!
 
Top Bottom