Keyless Entry

[Broosedamoose]

Still nothing! It doesn't make sense! According to the wiring diagram, the LC Board receives the signal from the transmitter and sends a pulse to the relay to either lock or unlock the doors. I checked the F11 fuse and it's good. Even if it was bad, other things associated with the board would not work. I can get another SJB, or BCM, but it would need to be programmed to my truck. I even tried the sequence to add a new transmitter, but the doors did not lock/unlock to verify programming mode. What I'm not sure of is, does the LC Board in the SJB actually receive the signal or does another module receive it and send it to the LC Board. The diagram below just show "Sense", so I assume it "senses" the signal. Such a freaking headache!

 

[Broosedamoose]

I've never really seen electronics work perfect one minute, only partially work another and then fail completely! Electronics either work or they don't! Things in between electronic components, like corrosion, temperature, moisture, etc. are always the culprits. I had to have the truck towed to my mechanic because the PATS prevented me from starting her up. Mechanic ran some tests and tells me the PCM is dead. I have one on order but, I'm affraid to install it! If the problem turns out being one of the things I just mentioned, when we put it in it's going to just get fried again! You know when you just have a gut feeling that the issue not what you are looking at? That's where I'm at. Here is why:

The truck was running fine at the beginning, I pulled out the HU, all the speakers, the seats and the the carpet. I ran all new wire for the audio system, the E-fan, the brake controller and the trailer connector. I covered the interior walls and floors with sound deadening material, installed a new carpet, put the seats back in and then tested everything. At this point I was very disappointed with the new sound system because it just didn't sound as good as what I took out. I back-tracked, checked all my connections and everything was good. The system played, the truck started, the remote start worked. My daughter even used it for a couple days to get back and forth to school! I just needed to tie up some wires and play with the HU settings. I dropped her off at school one morning and took the truck for the day. I went to go work on the truck and the locks would not work using the transmitter! I had to use the key to unlock the doors. Now, at this point, the alarm system was in valet mode. I figured it might be the battery in the transmitter so I put a new one in. Still didn't work. I tucked the alarm module up in the dash and tied up the wires. I then spent some time playing with the HU settings. I had to go out so I locked up the truck and took the Explorer. When I got home, I got the keys, went out to the truck and the locks worked! I tried wiggling the alarm wires around, losened the seat bolt so I could check for a pinched wire, but couldn't duplicate the problem! I thought that maybe the connector on the alarm module that sends out a pulse to lock/unlock the doors wasn't in all the way and when I tucked it up under the dash it popped in. Everything was working as it should now, except I noticed the HVAC blower was not on even though the switch was. In the past when this has happened, I just tapped on the relay and it would kick on. Sure enough, I tapped the relay and the blower came on. So I got a new relay and figured it would fix that issue. While putting it in, I noticed the E-fan was not running. I tapped the top of the BJB and the fan flicked on and off. I tapped it again and the fan came on! I'm pulling power for the fan relay with a fuse tap from the F43 fuse (EVAP valve, PCV valve, IAC valve, MAF/IAT sensors, O2 sensors, EGR valve). This does not power the fan, just the relay. After that, everything was working, as far as I could tell. I wasn't able to find the issue so I figured it was just a bad connection. There was no corrosion on the fuse legs or the fuse tap. That afternoon I showed my daughter how to put the alarm in/out of valet mode and handed her the keys. Oh, I also installed her dash cam but it was connected to the 12V PO because I had not received the hardwire kit. Five minutes after giving her the keys, I sent her out to the truck to pair the camera to her phone. I heard the alarm go off and thought she had forgotten to disarm the alarm before opening the door, but she said the transmitter wasn't working again! So now the siren is blarring, the overide button won't work and I'm aggrevated! I grab the wire cutters, cut the zip-ties holding the alarm tucked in the dash and disconnect everything! The alarm is off and the starter disable is disabled. Truck starts right up, fan comes on and the blower works. So I tell her to just use the key for now until I can get it figured out. We head off to the gas station so I can show her how to fill and when we get back in the truck, it won't start! Now the PATS light is blinking and the odometer is blank! WTF!!! Now I'm really aggrevated! I stick the key in the ignition and she fires up! This is what throws me! How does it work one second, not work and then work again? We get back to the house and I start the truck like ten times. I'm getting really pissed because my daughter has been patiently waiting for me to finish the audio system and this crap starts. She wants the truck so much, mostly because it "was Dad's truck" but also because of the new audio system and because when she was able to take it to school, all the boys were checking it out! One kid offered her $3K for it! Even one of the dads was checking it out and saying it's a nice truck! So, needless to say, I was really pissed off!!! The "PATS no start" happened to her at school a couple days later but, it eventually started and she drove it home. When I tried to start it, it was dead! I must have tried twenty times! My mechanic came and picked her up and took her to the shop. When I stopped by the next day he said the PCM was bad. It's getting battery voltage at the connectors and all the grounds checked out. So, now I'm back to the BJB and wondering if there is corrosion somewhere. A couple fuses and relays have some discoloration but nothing major. I was going to just replace the whole box until I found out how involved it would be! I just don't know if there is corrosion underneath the sockets or something that fried the PCM. I keep thinking about how the fan and blower kicked on and off when I tapped the top of the box. If I put the new PCM in and it fries, I'm out a lot of cash and back to square one! God I hate electrical gremlins! Well, that's where I am at right now. Sorry for the long post but maybe you can think outside of the box and see something I'm missing!

 

[Curious Hound]

I've never really seen electronics work perfect one minute, only partially work another and then fail completely!

I've been working on machinery since 1982 and I've seen it a lot. Intermittent problems are difficult. Capacitors go bad, solder joints crack, heat and vibrations cause things to expand and contract - make contact and lose contact.

You may have more than one gremlin. But, often, in cases like this it is a loose ground connection common to all the issues. Check all your grounds to make sure they have clean, tight connections and go back through everything you disturbed while doing your project.

 

[Rick W]

I've never really seen electronics work perfect one minute, only partially work another and then fail completely! Electronics either work or they don't! Things in between electronic components, like corrosion, temperature, moisture, etc. are always the culprits. I had to have the truck towed to my mechanic because the PATS prevented me from starting her up. Mechanic ran some tests and tells me the PCM is dead. I have one on order but, I'm affraid to install it! If the problem turns out being one of the things I just mentioned, when we put it in it's going to just get fried again! You know when you just have a gut feeling that the issue not what you are looking at? That's where I'm at. Here is why:

The truck was running fine at the beginning, I pulled out the HU, all the speakers, the seats and the the carpet. I ran all new wire for the audio system, the E-fan, the brake controller and the trailer connector. I covered the interior walls and floors with sound deadening material, installed a new carpet, put the seats back in and then tested everything. At this point I was very disappointed with the new sound system because it just didn't sound as good as what I took out. I back-tracked, checked all my connections and everything was good. The system played, the truck started, the remote start worked. My daughter even used it for a couple days to get back and forth to school! I just needed to tie up some wires and play with the HU settings. I dropped her off at school one morning and took the truck for the day. I went to go work on the truck and the locks would not work using the transmitter! I had to use the key to unlock the doors. Now, at this point, the alarm system was in valet mode. I figured it might be the battery in the transmitter so I put a new one in. Still didn't work. I tucked the alarm module up in the dash and tied up the wires. I then spent some time playing with the HU settings. I had to go out so I locked up the truck and took the Explorer. When I got home, I got the keys, went out to the truck and the locks worked! I tried wiggling the alarm wires around, losened the seat bolt so I could check for a pinched wire, but couldn't duplicate the problem! I thought that maybe the connector on the alarm module that sends out a pulse to lock/unlock the doors wasn't in all the way and when I tucked it up under the dash it popped in. Everything was working as it should now, except I noticed the HVAC blower was not on even though the switch was. In the past when this has happened, I just tapped on the relay and it would kick on. Sure enough, I tapped the relay and the blower came on. So I got a new relay and figured it would fix that issue. While putting it in, I noticed the E-fan was not running. I tapped the top of the BJB and the fan flicked on and off. I tapped it again and the fan came on! I'm pulling power for the fan relay with a fuse tap from the F43 fuse (EVAP valve, PCV valve, IAC valve, MAF/IAT sensors, O2 sensors, EGR valve). This does not power the fan, just the relay. After that, everything was working, as far as I could tell. I wasn't able to find the issue so I figured it was just a bad connection. There was no corrosion on the fuse legs or the fuse tap. That afternoon I showed my daughter how to put the alarm in/out of valet mode and handed her the keys. Oh, I also installed her dash cam but it was connected to the 12V PO because I had not received the hardwire kit. Five minutes after giving her the keys, I sent her out to the truck to pair the camera to her phone. I heard the alarm go off and thought she had forgotten to disarm the alarm before opening the door, but she said the transmitter wasn't working again! So now the siren is blarring, the overide button won't work and I'm aggrevated! I grab the wire cutters, cut the zip-ties holding the alarm tucked in the dash and disconnect everything! The alarm is off and the starter disable is disabled. Truck starts right up, fan comes on and the blower works. So I tell her to just use the key for now until I can get it figured out. We head off to the gas station so I can show her how to fill and when we get back in the truck, it won't start! Now the PATS light is blinking and the odometer is blank! WTF!!! Now I'm really aggrevated! I stick the key in the ignition and she fires up! This is what throws me! How does it work one second, not work and then work again? We get back to the house and I start the truck like ten times. I'm getting really pissed because my daughter has been patiently waiting for me to finish the audio system and this crap starts. She wants the truck so much, mostly because it "was Dad's truck" but also because of the new audio system and because when she was able to take it to school, all the boys were checking it out! One kid offered her $3K for it! Even one of the dads was checking it out and saying it's a nice truck! So, needless to say, I was really pissed off!!! The "PATS no start" happened to her at school a couple days later but, it eventually started and she drove it home. When I tried to start it, it was dead! I must have tried twenty times! My mechanic came and picked her up and took her to the shop. When I stopped by the next day he said the PCM was bad. It's getting battery voltage at the connectors and all the grounds checked out. So, now I'm back to the BJB and wondering if there is corrosion somewhere. A couple fuses and relays have some discoloration but nothing major. I was going to just replace the whole box until I found out how involved it would be! I just don't know if there is corrosion underneath the sockets or something that fried the PCM. I keep thinking about how the fan and blower kicked on and off when I tapped the top of the box. If I put the new PCM in and it fries, I'm out a lot of cash and back to square one! God I hate electrical gremlins! Well, that's where I am at right now. Sorry for the long post but maybe you can think outside of the box and see something I'm missing!

Man, the fugitive gremlins really can make you crazy, the intermittent stuff. Sipping my Easter morning coffee, this flipped me into the way back machine and reminded me of a couple things.

I bought a very exotic, very expensive car for very little money because the battery would go dead if you didn’t drive the car for 24 or 48 hours. Half a dozen good mechanics and the dealership could not find the fugitive draw down. I searched for weeks and could not find it. It was parked in the back of the shed of miracles, which is two cars wide, and two cars deep, so, every day when I parked my car, it was staring me in the face. One night when I came home, the light from the garage door opener had burned out. When I turned off my headlights, there was a dim light underneath the car. Turns out the switch that illuminates the light under the hood was universal and could be wired normally open or normally closed. It was wired backwards, so the light was off when the hood was up, and it would go on when you close the hood. So when you open the hood to look for the loss, you never found the loss. I ended up gaining about 20-25 grand on the value of that car because my garage light burned out.

The other memory was a 1956 Dodge 3/4 ton service truck, an old Bell telephone truck, with an aluminum service body. I wish I had that thing today! It had the winged hood, a flathead six, and it was 6 volt. Rust free and, mechanically, it was in very good condition, but about once a month or once every other month, something would go dark or something would short and start burning. It had the antique braided cotton coated wires. Well, I should say it used to have them, because half of that braided cotton was fitted off and gone when I had it. So one day, it finally annoyed me enough, that I bought a spool of wire and I rewired the whole truck. I mean everything. It took about 2 1/2 hours because that truck only had about a dozen wires in it. Headlights, tail lights, heater motor, and a couple things under the hood. There was no radio, and the wipers worked off the vacuum, which was a hoot.

And yes, I painted it with rustoleum.

This isn’t my truck, but it’s a pretty close. The top of the bed had a sliding roof and a fold down door so you could stand a refrigerator in it, or you could lock it up tight. I bought it for 200, had a mechanical problem fixed for 100, painted it for 20 bucks, redid the wires for $10, and sold it for $1200 about four years later! Who can say that about anything today!