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Alarm issues not locking and going off randomly

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Old Aug 5, 2025 | 02:00 PM
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Default Alarm issues not locking and going off randomly

Finally got key fobs programmed and working but the horn honks when locking with the fob and the doors don’t all lock with the key. To lock it I have to use the dash button and then lock the drivers door with the key. I have the hood disconnected and tried disconnecting the door sensors one by one and all togather with no change.

Until a few days ago it just started working with the fob locking unlocking perfectly. I was stoked but then the alarm started going off randomly within the hour.

Read about resetting with the key lock unlock 3x and now it’s not working again. Should of left it alone and tried disconnecting the interior sensor first I guess.

Any clue why it would start working and then not after resetting? What else could I do to test it besides replacing the bcu which can only be done by sending it out for reprogramming.
 
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Old Aug 5, 2025 | 03:57 PM
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Horn honk means it is seeing an open condition. Be it a door, cargo door, or hood switch. Dome lights stay on for a good bit before timing out?
 
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Old Aug 5, 2025 | 07:01 PM
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In the past when this happened to me it meant a door latch went bad and needed replacing.
 
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Old Aug 6, 2025 | 04:31 AM
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Alright well today it started working again.

Tried it again this evening, I locked it with the dash button then it locked with the fob no horn also tried locking with the key and it locked all doors which it wasn’t doing just the horn and no locking.

Thing is the alarm is going off after an hour or so randomly. I tried locking it with the key hoping it would disable the interior sensor and it still went off.

Could one of the door sensors be faulty and triggering the alarm? Honestly just want to be able to lock and unlock it don’t really need the alarm although it would be nice. Stumped…
 
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Old Aug 6, 2025 | 10:02 AM
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Originally Posted by AinaRover
Alright well today it started working again.

Tried it again this evening, I locked it with the dash button then it locked with the fob no horn also tried locking with the key and it locked all doors which it wasn’t doing just the horn and no locking.

Thing is the alarm is going off after an hour or so randomly. I tried locking it with the key hoping it would disable the interior sensor and it still went off.

Could one of the door sensors be faulty and triggering the alarm? Honestly just want to be able to lock and unlock it don’t really need the alarm although it would be nice. Stumped…
If it's a bad latch, usually one of the doors remain unlocked while the rest lock. Could be a bad or misaligned hood close sensor too.
 
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Old Aug 6, 2025 | 01:25 PM
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Do you have the 2 alarm sensors inside the cabin? One above the drivers head & one toward the rear? I've had bugs inside the D2 set those off.
 
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Old Aug 7, 2025 | 07:08 AM
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Sounds like a lazy lock motor to me. I doubt it has anything to do with the fob, even one lock actuating means the fob is doing its job and something is failing mechanically. Locking twice may be inciting one of the locks to complete its travel. You'll need to troubleshoot which of the locks isn't cooperating and repair or replace it (them). Lock the truck and check all the doors, watch the pins go up and down, etc. Flaky locks is pretty common as these trucks are getting beyond 20 years.
 
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Old Aug 10, 2025 | 10:14 PM
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Starting to think it’s a battery issue, after a long drive it tends to lock fine and I can leave it for 15-20min no alarm.

When it’s locking it’s locking all door and rear perfectly fine. I do have the hood sensor disconnected because the boot is ripped and it’s proably no good.

After about an hour it’ll go off and then it doesn’t lock with the remote or key any more just honks. I tried before disconnecting door locks one by one the all togather and it still honks.

The battery has been drained completely a few times from sitting so going to see about getting a new battery in and report back.
 
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Old Aug 11, 2025 | 12:32 AM
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Originally Posted by AinaRover
"I do have the hood sensor disconnected because the boot is ripped and it’s proably no good."
You do realize simply disconnecting the hood switch = that is an "open" condition unless you have the harness jumpered into thinking the hood is closed. Like I said in a previous reply the LR MUST see the hood, all 4 doors, and the rear cargo door as "closed" to properly arm the alarm. A horn beep is telling you that condition is not made when the horn sounds when you use the remote to lock it. Plug the hood switch back in and see if arming it causes the horn to sound via the remote? When the switch is simply unplugged that creates an "open" circuit.
 
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Old Aug 11, 2025 | 01:44 AM
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Didn’t realize this at all. I had read in another thread that if the hood switch is malfunctioning you can just disconnect it and if the alarm works it’ll confirm that’s faulty.

Still interesting that it tends to work after a longer drive even with the hood disconnected. Locks with the fob and no beep.

I have tired it connected before but will try again and also try jumping it if no change. Appreciate the help!
 

Last edited by AinaRover; Aug 11, 2025 at 01:47 AM.
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