Keyless Entry

[Broosedamoose]

My keyless entry quit working all of a sudden. It was working fine. I went out to the truck 5 minutes after getting out and the doors wouldn’t unlock. I put a new battery in the remote but it didn’t work. I tried my spare, also with a new battery and it still didn’t work. So I just used the key until I had time to check it out. Two days later, after the truck had been sitting overnight, I went to leave and pressed the button and it worked! Out of the blue it just started working! Now, about a week later, it quit again! I thought it might be the alarm module so I pulled it out but it still doesn’t work. Where do I start?

 

[rumblecloud]

I've never had to mess with mine, but it sounds like a loose wire, but that would be too simple. The only moving parts are what's in the door. So I would start there. Again, not an expert, but that's where I would start.

 

[97RangerXLT]

I would say that the issue is an intermittent ground or the RKE module itself. also check the fuses to make sure no green nasties are forming on or around them, likely other issues will pop up if that is the case.

AJ

 

[pentode]

I'll just offer an alternative possibility. My remotes (I have 3) periodically stop working and it's always the battery in the remote making poor contact. It seems to be a combination of the terminals losing their springiness and possibly some light corrosion, but I just bend the terminals a bit to make better contact and they'll work for a year or so. It seems like a little impact, such as dropping the keys on the ground, often seems to provoke the failure.

Just putting it out there - I'd rather have that problem than bad wiring harness.

 

[Rick W]

How healthy are your batteries? May sound silly, but I have a similar repeat problem with the remote on my garage door opener key fob, the same thing.

What I finally traced it down to were the cheap batteries I buy, and I always have a bunch of keys in my pocket at the same time.

Batteries: if you go to the store and buy a Duracell or whatever, they want $5 or $10 for two or three batteries. If you order the same batteries online - no name - you can get a dozen or 20 or more for the same price, but you have to wait a few days to get them. I just bought 50 of one of the little ones for $11 delivered, and split them with the cute little brunette. I’ve had really good luck with those batteries, but one out of 20 will be a dud or will be low power.

Keys in my pocket: each of the six vehicles I drive has a separate key ring, and I only bring the one I’m using with me, but if I’m fiddling in the yard, I might have three or four rings in my pocket. My regular key ring has a 8-9 keys on it, an a little knife, etc., and it’s actually a combination of two rings. And half the times I go out, I’m carrying keys for one of the properties or such also. There are two key fobs or more in my pocket at all times, one for the garage (it’s actually a four button, four garage/function controller), and one for the security system on my house, and a couple of the vehicles have remote door openers or alarms. I’ll bet that once a week I trip my alarm or I open the garage or a car vice versa when I’m bending over or I sit down and the keys somehow push a button on something. I upgraded the multifunction 4-button remote to one that has a sliding cover a couple years ago, but the cover gets worn after about six months, and it will slide up and down in my pocket. Keep your dirty thoughts to yourself. I actually put a small piece of thin but hard rubber over the panic button on my alarm, and wrapped it with friction tape, so I don’t set it off by accident.

The other thing on the 4-button garage door opener: sometimes, even with a brand new battery, it won’t open after a couple days, and then the next day it will work. I think what happens is the button is getting pressed with the jumble of keys in my pocket, and drains the battery quickly (as if you held it for an hour or such), but then when the button is not depressed, it’s chemistry balances out and regains some power, and works again. Another reason I suspect that is after it starts working again, sometimes it will only work if I get closer and closer to the garage - obviously there was some power loss.

It’s either that or the tinfoil inside your hats are different thickness and draws all the signal away sometimes. Try wearing the same hat for a week at a time and see if that helps.

My 2 cents, hope it helps.

 

[RobbieD]

Except for the really old ones, RKE systems use a changing code with each use for security. When changing a remote battery you may have to press the button several times so that the transmitter (fob) and receiver (RKE module) can get resynchronized.

 

[Broosedamoose]

As for batteries, I said in my original post I put new batteries in both transmitters. I don’t think it’s in the door because that would only affect that door, not the other door or the alarm. As for the RKE code changing, I tried pressing the button several times and it didn’t work. I looked for corrosion when I checked the fuse. Maybe a loose wire. I’ll have to go right to the module to see if it is putting out a pulse or if it’s dead.

 

[Broosedamoose]

Now the HVAC doesn’t work and intermittently the truck won’t start because of the PATS. Sometimes it starts right up, but sometimes it won’t and the theft light blinks! If I keep trying, it will eventually start. It makes no sense! I’ve checked the fuses and they are all good. I’m at my wits end! I did just install a new HU so I’m going to pull it out and see if there is a loose wire. I don’t see how that would have anything to do with the RKE or PATS but who knows.

 

[Broosedamoose]

I pulled the new HU and didn't find anything. I looked for the RKE module, which is suppossed to be in the passenger kick panel, but can't find it. The doors will lock/unlock with the door switches, just not with the transmitter. It makes no sense! I've never had an issue with the truck until literally, 5 minutes after giving it to my daughter! I don't know what else to do. She got stuck at school yesterday because the PATS wouldn't let her start the truck! After about 10 tries it finally decided it was the right key and let her start the truck! It's an original key too! I just bought a wiring diagram manual off eBay to try and trace out the wires. Electrical issue suck!

 

[rumblecloud]

Electrical issue suck!

I second the motion.

 

[pentode]

You mentioned new head unit - did you wire that into the existing harness or grab power from somewhere else? Assuming you used the existing harness, it almost has to be that something in the wiring harness got disturbed during the installation. It really has the sound of the classic wire-chafing-over-20-years phenomenon, either a power wire intermittently grounding or a ground rubbed through. I'd pull the head unit, see if you can get it to misbehave, then wiggle wires around to see if it comes to life, or if it's working, wiggle wires and see if you can make it fail.

 

[Rick W]

Over the 50 or 60 years I’ve been doing all this silliness, one thing I’ve learned is if you fix something or change something, and then you have a problem, go right back to the last thing you touched/fixed. I don’t believe in coincidences. Then take a look at where you might’ve been resting your elbows or such when you climbed in to do whatever you were doing and make sure you didn’t knock something loose like that.

If you changed the head unit, you may want to just disconnect it to try and isolate the problem. Your girl won’t have radio for a few days, but see if that solves the problem. If it doesn’t, she’s without radio a couple days, but if that does solve the problem, obviously you need to do more homework on that head unit

Hope it helps

 

[Broosedamoose]

Over the 50 or 60 years I’ve been doing all this silliness, one thing I’ve learned is if you fix something or change something, and then you have a problem, go right back to the last thing you touched/fixed. I don’t believe in coincidences. Then take a look at where you might’ve been resting your elbows or such when you climbed in to do whatever you were doing and make sure you didn’t knock something loose like that.

If you changed the head unit, you may want to just disconnect it to try and isolate the problem. Your girl won’t have radio for a few days, but see if that solves the problem. If it doesn’t, she’s without radio a couple days, but if that does solve the problem, obviously you need to do more homework on that head unit

Hope it helps

I guess I should have said that the first thing I did was go back to the HU. I was just thinking of what I did associated with the door locks. I pulled the HU out and completely disconnected everything. I checked all the wires back to the connector and as far as I could see. There is nothing there and the doors still don't lock/unlock. I even pulled the AM alarm module out to see if that was the issue. Nope! It just seems strange that the PATS act up like it does. I've worked with electronics all my life and that's something that either works or it don't! I could see if it had a battery or something but if a module is bad, it doesn't come back to life. And, the locks are a constant, the PATS issue is random. I've had the truck all day today and must have started it 10-15 times and it started every time. So I can only assume that whatever it is, it's causing the PATS module to lose power intermittently. Is there a relay associated with the PATS module that could be failing?