Power door locks

[Madlh24]

Just got the jeep last week. The power locks will work the first couple of times, unlock, lock, but then it seems like they lose power...? Every time I use the switch, doesn't matter which switch, they function less and less, As if the battery is dying. So if I unlock they work, but if I lock and then unlock again they don't, it sounds and looks like they want to unlock,i can see the finger locks wanting to budge but nothing. But, if I wait 5 minutes or so, they work again. Also, it doesn't always unlock the tail gate. Especially if I accidentally hit lock first before unlocking, then I HAVE to wait like 5 minutes before it can unlock the tailgate again. I replaced the 3 relays under the dash and nothing changed. I'm assuming a bad ground somewhere? The battery looks fairly new, the date stamp is from February this year. This happens whether the car is on or off.

 

[uss2defiant]

same issue w/ the key fob?

 

[Madlh24]

The PO didn't have the key fob, but from the build sheet I got from Chrysler it should, I'm working on getting a replacement.

 

[uss2defiant]

interesting....
any other accessories that might indicate a bad batter?
might just want to check the battery anyways just in case, the AZ heat doesn't help w/ batteries.

 

[Madlh24]

interesting....
any other accessories that might indicate a bad batter?
might just want to check the battery anyways just in case, the AZ heat doesn't help w/ batteries.

Everything else works fine,I figured that if the battery can start the engine no problem the draw from locks should not make a difference, especially considering their behaviour doesn't change when the car is on with everything else running.

I'll get the battery tested today just to make sure though.

 

[uss2defiant]

so either D/S or P/S switch, you see the same issue?

 

[Madlh24]

so either D/S or P/S switch, you see the same issue?

Yes

 

[uss2defiant]

what year is your jeep?

 

[Madlh24]

what year is your jeep?

2004

 

[Billwill]

Does this happen with all five doors ie. 4 doors and rear tailgate?

If your rear tailgate has the ability to lock/unlock using the key on the tailgate handle does this work well or is it also sluggish?

You need to put a voltmeter over one of the locks and see if you are getting +12 volts across it or if there is a voltage drop somewhere. This voltage flips over as it opens or closes so the ground and +12 volts swap over....check the +12 volts relative to the ground on the motor and also check the +12 volts on the motor relative to a good clean chassis point...this should show if the door locks are getting a weak ground....which they get from the BCM!

The BCM...on the rear side of the internal fuse panel....is responsible for most of this locking/unlocking action.

 

[Madlh24]

Does this happen with all five doors ie. 4 doors and rear tailgate?

If your rear tailgate has the ability to lock/unlock using the key on the tailgate handle does this work well or is it also sluggish?

You need to put a voltmeter over one of the locks and see if you are getting +12 volts across it or if there is a voltage drop somewhere. This voltage flips over as it opens or closes so the ground and +12 volts swap over....check the +12 volts relative to the ground on the motor and also check the +12 volts on the motor relative to a good clean chassis point...this should show if the door locks are getting a weak ground....which they get from the BCM!

The BCM...on the rear side of the internal fuse panel....is responsible for most of this locking/unlocking action.

There is no key cylinder on the tail gate.The sluggishness is across all the locks including the tailgate. The sluggishness only appears after having activated the locks a second time.

I will volt check as soon as I get my hands on a multimeter. I accidentally left my current one in the car and it got all kinds of warped(120°F outside) and now the selector won't turn.

 

[uss2defiant]

i wonder whether it's an issue w/ the switch.
in the FSM there's a door lock circuit protection.
If the switch is actuated continuously for more than 5 seconds, the bcm will turn off the driver to the power lock.

follow the debugging steps in the fsm.
it's section 8N - power locks.

Index of /manuals/Jeep/KJ
even though there's no 04 manual, just use the 03.

btw how south are you?

 

[Madlh24]

i wonder whether it's an issue w/ the switch.
in the FSM there's a door lock circuit protection.
If the switch is actuated continuously for more than 5 seconds, the bcm will turn off the driver to the power lock.

follow the debugging steps in the fsm.
it's section 8N - power locks.

Index of /manuals/Jeep/KJ
even though there's no 04 manual, just use the 03.

btw how south are you?

Wouldn't the 05 manual be closer? That's what I've been looking at. I'll take a look at the 03 as well though.
I wouldn't think it's that though, as i would assume the power cutoff would be a complete cutoff. When the locks start acting up they still wiggle when activated, they just don't actually lock, unlock, I can hear the actuators trying to work only they sound like they don't have enough juice. Once I let it sit for like 5 seconds they work again, albeit very sluggish,I still have to wait like 5 minutes before it will unlock the tailgate again though.

I'm almost as far south as it gets. Yuma. Only 20 or so miles from the border. But, I Bought the jeep in Phoenix.

 

[uss2defiant]

don't think it would matter, 03 or 05.

I guess you'll have to go down the list of things to eliminate.
Have you measured the resistance value of the switch yet?
There's a table in the FSM w/ the values.


ahhh..... i guess you're closer to mexico than I am.
i would help you if you were closer to me.

 

[Madlh24]

Ok, I'm getting a new symptom, sometimes the driver's side switch will not do anything when I push it up. And sometimes it will lock instead of unlock. Worn out switch causing high resistance?

 

[uss2defiant]

Have you measured the resistance value of the switch yet?
There's a table in the FSM w/ the values.

I would also disconnect the P/S lock switch if you're just looking at the symptoms just so you can pinpoint a specific switch.

 

[Madlh24]

Have you measured the resistance value of the switch yet?
There's a table in the FSM w/ the values.

I would also disconnect the P/S lock switch if you're just looking at the symptoms just so you can pinpoint a specific switch.

Haven't gotten a hold of a multimeter yet, none of my friends have one and my dad does but he's in the process of moving into a new house and all his tools are deep inside a moving truck.

 

[Billwill]

Haven't gotten a hold of a multimeter yet, none of my friends have one and my dad does but he's in the process of moving into a new house and all his tools are deep inside a moving truck.

Buy a cheap Multi meter....you do not need anything fancy or extremely accurate for your needs.

The 2003 Service Manual should be used for your 2004 KJ....a lot of changes made on the 2005 models!

 

[grunt3327]

I have a 2010 Jeep Liberty that has been not locking, but alarm works. The auto door locks do not work when driving. I have checked out the fuse panel under the hood and found that the M38 was blown. I replaced the blown fuse and not I can hear the doors trying to lock, but they do not. Also another kicker, is when I was driving I accidentally hit the door lock with my elbow. I then clicked the unlock and it unlocked, but when I hit the lock button (either of the doors) it won't lock. I also tried unhooking the battery and waiting for 5 minute to reset things and that didn't work. Anyone have this issue?

 

[Scooter 1991]

I have a 2010 Jeep Liberty that has been not locking, but alarm works. The auto door locks do not work when driving. I have checked out the fuse panel under the hood and found that the M38 was blown. I replaced the blown fuse and not I can hear the doors trying to lock, but they do not. Also another kicker, is when I was driving I accidentally hit the door lock with my elbow. I then clicked the unlock and it unlocked, but when I hit the lock button (either of the doors) it won't lock. I also tried unhooking the battery and waiting for 5 minute to reset things and that didn't work. Anyone have this issue?

I have almost the same issue. My 2010 will not lock with the remote but it will unlock with the remote. It also will arm the alarm but wont lock the doors. Anyone know what may be the cause?