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Well, that doesn't make a lot of sense. Because why would me cutting off one of the leads on the new switch, drilling a hole through the back of the new switch and soldering it directly to the metal lead (where it was presumably already going while encased in the plastic) make the resistance any different from how the new switch was originally wired? All I know is that this hack works as I've done it to 3 new switches now. All of them had no resistance brand new out of the box, but all have resistance now after I hacked all 3.
 

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Ok so I ordered your switch Doorman #901-470 .
It is exactly the same switch bit for a different Chrysler ( the caravan I beleive).
Instead of the required 1.5ohms resistance when closed I measured 4.8 kohms (that's why it might seem broken if you don't measure resistance) . To make it work I followed you process and drilled a hole. Instead of a simple bridge, I added a 2.2kohms resistor in parallel of the resistor to the Doorman #901-470 and successfully achieved a total of 1.5kohoms resistance required by the fiat 500 abarth 2012 bcm to recognize a closed hatch button. All good it's now as new.
 

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Ok so I ordered your switch Doorman #901-470 .
It is exactly the same switch bit for a different Chrysler ( the caravan I beleive).
Instead of the required 1.5ohms resistance when closed I measured 4.8 kohms (that's why it might seem broken if you don't measure resistance) . To make it work I followed you process and drilled a hole. Instead of a simple bridge, I added a 2.2kohms resistor in parallel of the resistor if the Doorman #901-470 and successfully achieved a total of approximately 1.5kohoms resistance required by the fiat 500 abarth 2021 bcm to recognize a closed hatch button. All good it's now as new.
Excellent, glad you got it to work!
 

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My girlfriend's broke too. Her Fiat is a 2016 500x. The rubber boot that goes on the switch became unglued from the switch. I tried to glue it back 3 times, using two different type glues, but ultimately it wouldn't stick and eventually kept falling off. Unfortunately over the past couple decades, there's not too many glues that will stick to plastic and or rubber anymore. So good luck on finding one that will stick. The switch will still work even with the rubber boot cover off. However, be very careful that the plastic faceplate to the switch (not the rubber boot) doesn't come apart and fall off. If it does, the inner spring will fall out and not make the switch work, even if you are able to put the plastic faceplate back on without the spring. If that happens, you can easily still activate the switch and open the hatch by placing a small piece of aluminum foil across the two metal leads inside the switch, which are located on both sides of where the spring was. The actual switch is held in to the hatch handle body by 4 small clips (two on top of the switch, and two on the bottom of the switch), which snaps it into the rear hatch handle body. Use a small screwdriver or thin putty knife to lightly pry it out. Once pride out, it will still be hanging there by the two electrical wires attached to the switch. Don't settle just yet on purchasing the entire rear hatch handle assembly for $150+. I searched around on Fiat sites and found what appears to be a generic replacement switch with the wire connector and attached rubber boot. Although the site says this switch won't fit her 2016 500x, it looks nearly identical with the exception of different coloring on the two wires. The price was cheap, really cheap at $11.81 with free shipping. I just ordered it and will be further working on this in a few days when it arrives.
 

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Did the generic part work? If so where did you order it from? Do you possibly have the part number too? Thanks in advance for your reply.
 

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I wrote a detailed post in this thread you must have missed. See this link and let me know if you have more questions.

 

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There is a way to fix the trunk switch issue. I converted mine to mechanical cable pull to open the trunk. I don't have any pictures of it, sorry. I drilled a small hole in the side of the trunk latch mechanism and put a large gauge wire (cut bike spoke) with a hook end over the latch mechanism. It is long enough to go outside the latch. loop on the end of wire. Then a bike brake cable with housing fed through the trunk out to where the switch is. Remove entire switch button and rubber cover. end of cable comes out where switch was. Finish end so you can pull the cable. When not needed put wire up into cavity of switch. This is not perfect and has not been refined. Because my switch failed and I could not get it to work even with custom repairs. Now I just pull the cable and opens the trunk. No electronics... No it will not lock but nobody knows until now how it works..
Hi, is there a way you can post pictures of what you did?
Thank you
 

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I did post several pictures in my original article showing what I did. Click on a couple links above this, and you will see all of the photos. Let me know if you can't, and I can further assist with guiding you to them.
 

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A lot of useful information in this thread, should you read continuity before and after the resistor?
I did not get any continuity between the contact of the switch and after the resistor I think that may be my problem.
 

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Some people here have said you can't read the continuity due to a safety mechanism built into the system in case there's a crash so the door doesn't open. But I don't believe that, because as I'm physically holding a new switch in my hand, and testing it with a voltmeter, there's no continuity in the line, and there should be. All I can tell you is, if you cut one of the wires on the new switch, open the switch up (carefully), drill a hole in the back of the switch, then solder that wire directly to the metal lead, then there will be continuity, and the switch will work. I've don't this to several switches already. DON'T be fooled by the dealers and spend $500 on the entire back panel that includes the switch, when you can just do the hack I have written about in this thread. Just follow my instructions and see all the attached photos of the work.
 

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My Abarth is a 2013. I can concur that reading a 1.5kohm resistor with a multi meter, will not read continuity. I tried the resistor bypass first. There was then continuity when the switch was depressed. The latch did not operate. I bench tested the latch with my cordless drill’s battery & it worked. My only option was to buy a new 1.5k ohm resistor and replace the one that burned out in my original switch. Now everything works as it should.

Hope this helps someone, as this thread has helped me.

BTW, I have plenty of resistors left and will ship anyone (1) to fix their switch if needed.
 
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