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Discussion Starter #1 (Edited)
Never a dull moment. Just used my trunk using the handle release at the store and when I got home it would not open. Tried both FOB's and the release button near the footwell. Tried reseting the valet functionally by turning the key in the drivers door counter clockwise 90 degrees three times fast. Nothing. Trunk lock is vertical, not set to valet.

From searching, I am guessing three things - 1) the switch in the handle, although there has been no signs or warning. 2) The wires in the wire boot have become frayed (again!) but this was always the false warning of the trunk open, or 3) the fuse.

I am thinking fuse because when I open the trunk manually with the key, the trunk is dark. No lights, BUT I guess this could be wires inside the boot for both the trunk release switch and the lights?

Hoping it's fuse. I will research where it is and which one.

Any experience/thoughts?
 

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I am not sure which fuse you talk about, there are three fuses for the central locking system in your glove box.
Didnt you have a code reader?
The trunk light is activated by the trunk switch.
Could be frayed wires yes...
 

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Discussion Starter #3
Ok, I looked inside the loom and its a mess, again. At least four wires broken completely and and three or four more frayed. Has to be it. I am going to do it right. Looks like I need to cut the rubber tube to get at the wires. It's a bitch.

Anyone know what gauge these little wires are? Need to order some wire and spicers.
 

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Discussion Starter #5
Thank you, nice find. I will use it verbatim. I don't know how he got the boot to slide down that far. I am struggling to slide it down to even get at the broken wires. Lastly, guess I am going to learn how to sober. Need to buy a gun I guess. Suggestions?
 

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Under the lift arms
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Id check the ground at the solenoid in the trunk lid first

then id confirm 12vdc To the solenoid,

Then id replace the solenoid

assuming you have power and ground At the motor for the lid,

IF you dont have ground and power at the motor for the trunk lid, Id repair that then move on..

IF you DO have ground and power At the connector for the truck motor,

micro switch (which this shouldnt matter because you have 2 other inputs * front button and key fob)

the motor
 

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Discussion Starter #7
Id check the ground at the solenoid in the trunk lid first

then id confirm 12vdc To the solenoid,

Then id replace the solenoid

assuming you have power and ground At the motor for the lid,

IF you dont have ground and power at the motor for the trunk lid, Id repair that then move on..

IF you DO have ground and power At the connector for the truck motor,

micro switch (which this shouldnt matter because you have 2 other inputs * front button and key fob)

the motor


Thanks B2. After pulling down the wire harness boot and seeing what a mess it is in there, pretty confident the the trunk light and the trunk release wires are broken. I’ll start there as this needs to be fixed right once and for all. Manual twist splice and electrical tape ain’t cutting it.


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Discussion Starter #8 (Edited)

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It will be fine...
 

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Wingnut
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a soldering iron of around 25 watt power is better for this job than a soldering gun. guns are too powerful for this. cleanliness of the joint to be soldered is essential. flux aids in this in that it boils off the outer layer of contamination of the raw copper, copper begins to oxidize immediately upon exposure to air. flux core solder works best vs a solid core solder and flux. solder is not an adhesive, it works by alloying a molecular layer of the copper with itself. tinning of the wire ends helps, in that the bond is created in that process, then when bringing the leads together, its just a matter of melting a solder bridge tween the two. basically, a better looking solder joint is a better joint, smooth even flow vs a lumpy surface, rough surface indicates cold solder bonds, where the alloying isnt completed. this can happen from contamination, or from improper heating of the surface. dont use the iron tip to melt the solder, use the heated copper itself to melt it.

edit...for this type joint, id use a chisel or "screwdriver" tip vs a pointed tip
 

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Im having the same problem.... almost. The light works and I can hear the solenoid move a tad bit... The first time the solenoid is activated either by the key, the switch inside or the handle, it seems like the first time is the strongest, then weaker, then nothing.... I took it apart and tried to see if there was anything I could do to fix or clean the solenoid... I couldnt. I also checked the wires in the boot. Only the red one had some insulation missing. All others were good. I ordered a VDO solenoid and it should be here on Friday. Ill post up the results.
 

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Discussion Starter #12 (Edited)
a soldering iron of around 25 watt power is better for this job than a soldering gun. guns are too powerful for this. cleanliness of the joint to be soldered is essential. flux aids in this in that it boils off the outer layer of contamination of the raw copper, copper begins to oxidize immediately upon exposure to air. flux core solder works best vs a solid core solder and flux. solder is not an adhesive, it works by alloying a molecular layer of the copper with itself. tinning of the wire ends helps, in that the bond is created in that process, then when bringing the leads together, its just a matter of melting a solder bridge tween the two. basically, a better looking solder joint is a better joint, smooth even flow vs a lumpy surface, rough surface indicates cold solder bonds, where the alloying isnt completed. this can happen from contamination, or from improper heating of the surface. dont use the iron tip to melt the solder, use the heated copper itself to melt it.

edit...for this type joint, id use a chisel or "screwdriver" tip vs a pointed tip
Awesome, great input. Should I use copper stranded wire? Having trouble finding the right product on Amazon. Here is what is in my cart, let me know what you think if you have a minute:

https://www.amazon.com/Stranded-different-colored-spools-included/dp/B00B4ZQ3L0/ref=sr_1_3?ie=UTF8&qid=1546866052&sr=8-3&keywords=stranded+wire
https://www.amazon.com/gp/product/B071G1J3W6/ref=ox_sc_act_title_7?smid=A3M1GAB2GO7D1D&psc=1
https://www.amazon.com/gp/product/B0756VKPTB/ref=ox_sc_act_title_8?smid=A1LH67TV3XN11S&psc=1
https://www.amazon.com/gp/product/B0759MHB45/ref=ox_sc_act_title_5?smid=ASECARC1KSKPX&psc=1
https://www.amazon.com/gp/product/B00EXLPLTW/ref=ox_sc_act_title_6?smid=A343L3F8RZU994&psc=1
https://www.amazon.com/gp/product/B008ZIV85A/ref=ox_sc_act_title_4?smid=ATVPDKIKX0DER&psc=1

The soldering kit comes with solder, but I can't tell if it's lead based which I want, so I added the 60/40 Lead/Tin solder. The solder tool doesn't look to come with a flat screw driver tip, but an angled one. This look ok? Is this the right flux? If this soldering tool is ok for my job, what temp should I set it to?

I am going to be doing this work in tight space with all 13 wires near each other. So I am going to have to be careful and patient. First time soldering, but I guess it's time I learn.
 

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Discussion Starter #13
Im having the same problem.... almost. The light works and I can hear the solenoid move a tad bit... The first time the solenoid is activated either by the key, the switch inside or the handle, it seems like the first time is the strongest, then weaker, then nothing.... I took it apart and tried to see if there was anything I could do to fix or clean the solenoid... I couldnt. I also checked the wires in the boot. Only the red one had some insulation missing. All others were good. I ordered a VDO solenoid and it should be here on Friday. Ill post up the results.
Given I have no lights in the trunk and the lock/unlock mechanism stopped working at the same time AND the wires are a mess, I think this is the best place for me to start.
 

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Your link to the 60 watt soldering iron kit is good, it's adjustable which is good.
The 22 gauge wire is a little bit too thin. 20 gauge would be better.
Make sure you get stranded wire, the more strands the better, the wire will be more flexible and last longer from flexing when you open/close the trunk.
Stagger the splices so you won't have them all bunched up in the same place.
 

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Wingnut
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ditto to what jimlev states, stranded wire has more flexibility, plus as the current is carried on the wire surface, and that stranded wire has more surface area than solid core, itll handle just a tad more power. yes to the 20 gauge wire, and everything else he said.
your solder selection is fine, 60/40 tin/lead ratio is the norm for this type of work, and it is rosin (flux) core wire, no additional flux needed.
any of the non pointed tips will work fine.
id start with the iron set to half power and do a few test splices and see if it needs to be varied from there. probably not.
are you looking at the heat gun to shrink heat shrink? itll work, but quickly moving a lighter flame back and forth under the joint will accomplish the same thing. practice a few times with your practice splices to get your timing right on the flame application.
you wont need the extra flux can, or the flux that comes with the iron.
 

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Discussion Starter #16
Your link to the 60 watt soldering iron kit is good, it's adjustable which is good.
The 22 gauge wire is a little bit too thin. 20 gauge would be better.
Make sure you get stranded wire, the more strands the better, the wire will be more flexible and last longer from flexing when you open/close the trunk.
Stagger the splices so you won't have them all bunched up in the same place.
Thanks Jim. Yeah, I realized after reading the DIY again that 18 gauge was suggested, so I updated my cart. Thanks for the confirm on the iron. I'll get everything ordered.
 

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Discussion Starter #17 (Edited)
ditto to what jimlev states, stranded wire has more flexibility, plus as the current is carried on the wire surface, and that stranded wire has more surface area than solid core, itll handle just a tad more power. yes to the 20 gauge wire, and everything else he said.
your solder selection is fine, 60/40 tin/lead ratio is the norm for this type of work, and it is rosin (flux) core wire, no additional flux needed.
any of the non pointed tips will work fine.
id start with the iron set to half power and do a few test splices and see if it needs to be varied from there. probably not.
are you looking at the heat gun to shrink heat shrink? itll work, but quickly moving a lighter flame back and forth under the joint will accomplish the same thing. practice a few times with your practice splices to get your timing right on the flame application.
you wont need the extra flux can, or the flux that comes with the iron.
Thanks again, I am going to go with 18 gauge stranded copper. Are you saying the solder I selected has the flux built into it? Yes, the heat gun was for the heat shrink, but I could use a heat gun in my toolbox anyway.

EDIT - actually, I think the lighter may be more targeted and the way to go where as the heat gun may blast too much given the wires are so close to each other.
 

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Discussion Starter #18
Here are some pics of the broken wires. I need to lookup what the wire assignments are.



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If you pull the rubber boot out of the body that will give you more room to replace the wires.
You can have splices back behind the body on one end.
If your real ambitious you can drop the trunk lid panel and have the other end of the splices inside the trunk lid.

Yes, the solder in your link said it has flux in it, but it wouldn't hurt to have some on hand to put on the wires before you "tin" them with solder before you solder the wires together..
If you've never soldered before this will make sure you have a good connection.
 

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Discussion Starter #20
Thanks Jim. I think I’m trying to peel back the rubber where I should be pushing it down like an accordion. Trying to avoid cutting it open.


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