key fobs aren't working

[txj2go]

I drove my Jeep 20 miles on Sunday. It has an almost new battery, about 1 month old. The batteries in my key fobs are less than a year old. The fobs haven't been exposed to cold recently and have never been wet. The Jeep is outside in 55 degree weather, both key fobs are in the house about 70 degrees.
I go outside today (Tuesday) to drive the Jeep and the key fob won't unlock the doors. I open with the key and the alarm goes off, I can't stop the alarm with the fob. After the alarm finally goes off I can't lock or unlock the doors with the fob. I go in the house and get the other fob, it won't lock or unlock the doors either. When I push the lock or unlock button on the fob the little red LED on the fob blinks one time.

Everything seems to be working correctly but the receiver in the Jeep or the computer is not cooperating. Is the receiver in the cabin or under the hood? If it is under the hood I can look to see if something has happened to it.

Sponsored

 

[Price1961]

Can you start the jeep with fab against the button? Is the button showing back lit?

 

[txj2go]

Can you start the jeep with fab against the button? Is the button showing back lit?

I can't get into the Jeep without setting off the alarm so I'm hoping there is a simple solution.

 

[Terrymo]

I think I would start with the simplest possible solution and replace the battery in the key fob…just in case. If it turns out not to be the fob battery you have a fob battery for when it does fail. Then move on to the next thing.

 

[JPAloha]

I think I would start with the simplest possible solution and replace the battery in the key fob…just in case. If it turns out not to be the fob battery you have a fob battery for when it does fail. Then move on to the next thing.

Sound advice. Not all batteries are created equally so very easy for a year old fob battery to be exhausted.

 

[Terrymo]

Sound advice. Not all batteries are created equally so very easy for a year old fob battery to be exhausted.

Agreed. I’ve been sure a battery must still be good, or a fuse looked good and have been wrong. I try to go with the cheapest and simplest possibility first. Hopefully that’s all it is for the OP.

 

[Medsker]

I'm just going to throw this out even though it's probably not why but when they try to steal these Jeeps I've read they hook up their computer thingy and erase the codes on your keys and "cut" new keys electronically. I wonder if they got half way through the robbery and something spooked them. Just a way "outside there" guess

 

[Kracka]

Replace your fob batteries...

 

[Bob Burd]

Btw, when you open the door and the alarm goes off, you should be able to turn it off by starting the Jeep by pressing the fob to the start button. Thereafter you can lock/unlock the car and start it as well. No alarm, but you can manage until the problem is resolved.

 

[txj2go]

Btw, when you open the door and the alarm goes off, you should be able to turn it off by starting the Jeep by pressing the fob to the start button. Thereafter you can lock/unlock the car and start it as well. No alarm, but you can manage until the problem is resolved.

I may try that.
The last time I set off the alarm I could not start the Jeep by pushing the button with the fob. I was in the middle of nowhere in Utah, sleeping in the back of the Jeep. It was around 30 degrees the next morning and my fob got cold. I tried unlocking the doors and the fob wouldn't do anything so I just opened the door. I couldn't figure out how to turn off the alarm and tried starting the Jeep with no luck. I put the fob in my pocket and let it warm up, then it started working again. And FWIW it can be very hard to find batteries for those fobs. I drove to several places in Denver and couldn't find the right battery. When I got back from the trip I drove around town to 3 or 4 places before I found them.

 

[hamiamham69]

I leave my key fob in the Jeep 24/7; it doesn’t get that cold here but lows in the teens at night and never had an issue

It is unlikely both fobs would fail at once but the cheapest, easiest, and quickest fix would be to change the fob batteries

Everyone’s case is different but so had the exact same “symptoms” Both fobs failed, alarm going off etc. I was able to press the fob against the starter button and turned off alarm…

long story short my aux battery failed: got something like 20 whole months out of that sucker. I did the aux battery delete - disconnect lead, pull fuse 42, use stop start eliminator plug in) and - voile - problem solved.

the aux battery is the bane of Jeep existence. It’s a ridiculously bad system

Rant over

 

[rossneill]

The key fob sensor is in the roll bar assembly if fob is working either way it needs to be checked at dealership jt computer may need reprogramming

 

[autotragic]

The key fob sensor is in the roll bar assembly if fob is working either way it needs to be checked at dealership jt computer may need reprogramming

It's going to be hard to keep a JL on the road 20 years from now when you can't get all the fancy sensors for it anymore.

So dumb.

 

[txj2go]

It's going to be hard to keep a JL on the road 20 years from now when you can't get all the fancy sensors for it anymore.

So dumb.

Every car or almost every car today is like that. We don't really know how long the fancy electronic systems will work but certainly the key fobs are a weak point. If necessary I suspect for the more popular cars there will be aftermarket products available to replace the factory electronics. Really it's just a matter of the programming in the system.

I took a break from work today to mess with my problem. I had tried numerous times throughout the day yesterday and neither fob was working. This afterrnoon I went out and checked under the hood to be sure no critter had been causing damage. I checked the main battery voltage and it is at 12.5V. I have no aux battery. I pulled out my key fob and it unlocked the doors without me doing anything else.

 

[Tyderian]

I took a break from work today to mess with my problem. I had tried numerous times throughout the day yesterday and neither fob was working. This afterrnoon I went out and checked under the hood to be sure no critter had been causing damage. I checked the main battery voltage and it is at 12.5V. I have no aux battery. I pulled out my key fob and it unlocked the doors without me doing anything else.

This sounds like the problem may have been a crusty battery node. It does happen. If the fob starts the Jeep with no issues going forward I would suggest investing in one of the packets of red battery terminal goo they sell at the part store. $1 is a small price to pay for the peace of mind.

Sponsored