Jeep Wrangler Forum banner

2018 Wrangler JK unlimited starting issue

19K views 44 replies 25 participants last post by  fengland 
#1 ·
Bought my first Jeep about 2 months ago. About 3 weeks ago I drove home from work, parked in the garage and went inside to get my wife to go eat. Go back into Jeep turned the key, dash lights came on but she wouldn’t crank. We went on to dinner in her car. After about 2 hours we came back home and I tried to crank it, cranked right up! The next morning I took it back to dealer so they could check it out. Nothing! This has now become an ongoing thing. They have it again now for the 4th time and don’t have a clue as to what is causing this. It seems that if I drive it from 20 minutes to an hour and stop it, it won’t crank for about 20 minutes. Someone help!
 
#2 ·
start with the battery. Make sure the clamps are fully seated to the terminals and tight! (10MM socket). Get some dielectric grease and put some on your battery terminals as well.

IF you still get the issue get the battery tested or try either getting another battery or battery booster pack (about the same price).

if your still having issues starting, check the starter wire. make sure its clipped in properly. again i would apply some dielectric grease to make sure It has good contact.

Edit: video on how to get at the starter:

https://www.youtube.com/watch?v=KXN4a0e3Pz4
 
#3 ·
We're sorry to hear this, newby55. We understand how this could be frustrating and your desires to have this addressed. We would like to see if there is any additional assistance we can provide while you are working with your dealer. Please send us a private message with your VIN, phone number, current mileage and servicing dealer.
Julie
Jeep Social Care Specialist
 
#5 ·
Yoga 44

I got the Jeep back yesterday, they installed a new valve body assembly in the Transmission. They seem to think this did fix my issue. The drive to work this morning will let me know for sure. I drive 45 minutes to work. If I get there this morning and park, turn it off and then it cranks right back... maybe just maybe that fixed it. That was their 4th time working on this same issue.
 
#11 ·
I too am among those frustrated with this. I have a 2018 JK with currently about 4k miles on it. I have noticed the same "won't start" problem. To date I've had about 2 dozen times it has done this. All were after (1) a several hour period of not driving and (2) a short ride to someplace close, with in 5 or 10 minutes and (3) no difference how long I let it sit it will not start. Then its' cool for the day. If I drive a distance, its fine ... I purchased this 6/25/18 and the first no start was 7/3/18, and continues since then. 7 times this week. Now, I did have an updated audio system put in with a back up camera, and dealer said they won't even touch it until it is back to stock ... reading all these posts, that sounds a bit bogus to me. Open for suggestions - planning to return to Best Buy and have them put it back to stock, then take to dealer. Love the jeep, hate the hastle.
 
#21 ·
I had the exact same problem, happened 6x last summer until I found the issue on this site and told them to check for it. They replaced the Temperature Range Sensor in the transmission and it worked fine until this last Saturday - it happened to me again when I was 40 miles away from home. so its in the shop again!
 
#14 ·
I am in the same boat with my 18 JK with the added bonus that it is stuck in 1st gear! It only has 1000 miles on it :-( I saw this post late and started a new thread emphasizing stuck in 1st gear.
 
#16 ·
I bought a new 2018K March 2018. All fine until Oct 5 and when I turned the key all the dash lights came on as normal, but no sounds of anything happening and the starter motor did not turn over the engine.

Did you ever get your no start fixed? I could use your solution possibly to solve my no start?
 
#17 ·
BagmoJK, I haven't run into a starting issue, however, I did experience an issue where it wouldn't shift out of first gear. This did however coincide with me adding a dual battery kit, to which the issue arose because of a loose connection at the TIPM. Odd that they were so sensitive to being moved, but if you have done anything under hood, may be worth looking at.
 
#18 ·
This is well know issue among the 2018 JK. Some have them some others dont. Mine was assembled in December 2017, and I bought it on July and it has not given me any issues, my brother had a 2018 Golden Eagle JK as a loaner from the dealer it left him stranded twice. He let it cold and it started.

This is the service bulletin number TSB 21-041-18. It is an issue pretty easy to replicate and it seems to happen more often in the mild to cold weather temp than in the hot weather. My bother had that loaner for a few weeks with weather around the 95F and no issues as soon the first cold front moved in and temps when down to the 65F the issue started to show.
 
#25 ·
I finally got my jeep back on Friday evening after they had it for a week. They were able to replicate the issue after I told them to drive it until the engine got hot, then turn off and try to start again (it didn't start for them). Same error code as this summer - they replaced the same part again. Hopefully this problem is solved but its been in the shop at least 3x for this exact same issue. The first time they couldn't figure it out, 2nd time they replaced a thermal sensor in the transmission, third time same thing. We will see....
 
#28 ·
A question in my mind?

Mine 2018 built in Feb is a automatic that is having the fail to start problem, to answer a above question.

But my questions is - does Jeep even know how many people are having this issues? If the dealer service adviser does not log the problem as a FAIL TO START no one knows and must they leave the problem record OPEN (not solved and closed) so Jeep knows they have a issue?

May we should make sure the dealer is doing their job and that they are forcing the issue up the Jeep SUPPORT latter for the product. Make them keep the problem record open, if that is even possible?
 
#29 ·
Mine 2018 built in Feb is a automatic that is having the fail to start problem, to answer a above question.

But my questions is - does Jeep even know how many people are having this issues? If the dealer service adviser does not log the problem as a FAIL TO START no one knows and must they leave the problem record OPEN (not solved and closed) so Jeep knows they have a issue?

May we should make sure the dealer is doing their job and that they are forcing the issue up the Jeep SUPPORT latter for the product. Make them keep the problem record open, if that is even possible?

Im guessing Jeep knows its a lot, because there is a TSB for it (21-041-18). My dealer had no idea this TSB existed, and, when I showed it to them, they got it to replicate, and got the valve body replaced.


IF they don't fix it, or can't duplicate it, the dealer will close the ticket as "could not duplicate concern" and that's that - it will remain.
 
#32 ·
@rjr9603 - yes, that is correct.


If there is a delay of greater than six seconds to change the trans temp display from actual trans temp to engine temp when going from D to P, then, you know you probably have this issue.


Once I got it fixed, I have not had any issue with it taking longer than 6 seconds to change.
 
#34 ·
Thanks for the replies guys!



Mine currently takes about four seconds on average to change over to coolant temp.

I stopped by the dealer this evening and set up an appointment for next Friday. The service writer said he knew nothing of the issue. I gave them the print out of what briggyman posted and gave them TSB number.

I will have to wait and see what they have to say. I know we have had the issue 6-8 times so far. The last two times I recorded on my phone.
 
#35 ·
2018 JK Trans Temp still jumps to engine temp after

I have a 2018 Wrangler purchased in March 2018. I also had multiple failures with the NO START conditions. Yesterday they performed the TSB to replace the trans valve body. So that is complete. Great.

I had hoped it would also resolve the Trans temp jumping to engine temp when i put it in park. But it did not and still EVERY TIME i put it in park, about 5 seconds later the trans temp jumps to engine temp(about 200 deg's), from about 165 deg's.

I showed this to the service adviser at the dealership, because it does this EVERY TIME. We are assuming this is a false error, because the trans temp DRIVING has acted normal since i bought it.

The service adviser did document the trans temp changing failure but because it did not force a error code, he is not doing anything about it and can not escalate it to Jeep. It is repeatable and does it every time, so why is this not a re-portable problem to Jeep?

How can i make Jeep aware of this problem that is easy to duplicate? I see others have commented about this same issue.
 
#36 ·
I had hoped it would also resolve the Trans temp jumping to engine temp when i put it in park. But it did not and still EVERY TIME i put it in park, about 5 seconds later the trans temp jumps to engine temp(about 200 deg's), from about 165 deg's.

.
Mine does the same, but it has never trigger the error code or failed to start. I have a 2018 Rubicon JK made in December 2017. I have had the Jeep for almost a year, lots of short drives like the type that makes the car fail to start and even though I have noticed the temperature Jump the Jeep has never left me stranded. I will be interesting to see if older models not included on TSB have the same type of glitch.
 
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