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Discussion Starter #1 (Edited)
Over the summer, I encountered the all too common problem that we've been having with the rear hatch not functioning. After doing a whole lot of digging, the only info I could find was about the wires splitting in the rubber sheath. Great! Now I can get started and have everything fixed in a day.

Here is what I found DSC_0251.jpg

Not too bad. No broken wires just a little water was found in that ?drain tube?; that must be the main issue: moisture causing contact. I sealed everything up and put the hatch back together. BOOM! FIXED!....or so I thought.

A while later, with a few damp days and the car sitting for a week unused, we're back to square one. Well, square -1 because now there is absolutely no function at all....the trunk shall remain closed forever. NOPE! With the help of actually reading a youtube comment, I actually found the release lever. 30 minutes later and everything was fixed. Its super easy, so the steps and pics are below.

This is only a guide if your exterior release button is not functioning but your wiring harness is intact....here we go.

1: GET YOUR HATCH OPEN
Pull off the interior panel. and look for this little bugger:
DSC_0011.jpg
See that tiny metal lever at bottom dead centre? That is you manual trunk release. Brilliant spot in my opinion. Push this down with a screw driver and open your hatch. Tie a string to this and hang it out the hatch every time you close it. fixed.

Kidding of course.

2: TEST THE CIRCUIT FOR FUNCTION.
With your hatch open, close the catch with your finger and unplug the wire harness from the hatch release here:
DSC_0010.jpg
Then, look at the end of the harness like an idiot for a few minutes while trying to remember what you did with you jumper wire; like this:
DSC_0009.jpg
This is the important bit; hold it like that. Exactly like that. If you don't, then the magical electrician in you brain will get upset and take a coffee break. Got it? OK. The left terminal is for the license plate lights and not important at all. The right terminal should be a black wire, and the middle terminal is the lead for the hatch release actuator. Shove your paperclip in those 2 holes( I know you're going to use a paper clip). If your magical electrician is not on break, you should hear little buzz-click sound. look at the catch, is it open? Good, now close the catch again and play with this a few times(its a neat sound). You've also just discovered where your problem is.

3. REMOVE THE SWITCH
Remove the 4 nuts that you saw in the first picture of step 2(they might only be finger tight, as mine were), then while holding the chrome exterior piece(switch assembly), pinch the black pinchy thing in the middle. Done. Now, Step 4.

4. Look at how dirty the back and bottom of the switch assembly are and say "f#$ing gross" before you clean it all up. While doing that, have a look at the connector; it should be super dirty too, and maybe a little corroded.

5. CLEAN YOUR CONTACTS
Scratch the contacts clean with what ever is handy and, gently, bend them down, or up, about 1/2mm. I did this because, as you may notice, the male terminals are a lot smaller than the female terminals(Oops. I guess Italian designers like to have art imitate life). Plug the wiring harness in and push the button.....buzz-click? If it made the noise, you are all done; If it didn't, you'll have to investigate further.

6. INVESTIGATE FURTHER
I don't know. I didn't have to. Please, if you did have to post your steps.
 

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Is there a way to drill a hole in the liner to expose the manual latch release?

Does it face outwardly?


TEdolph
 

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Discussion Starter #3
The lever faces inward. I suggest taking off the interior hatch trim and looking around;its always better to know more about your car.

I see where you are headed by wanting to drill a hole there. It's funny, if FIAT had put a hole there, even without any sort of label, I think we all would have figured out what it was for.
 

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The lever faces inward. I suggest taking off the interior hatch trim and looking around
You CAN'T remove the trim completely with the hatch closed, but removing all the retainers and clips lets you lay it down enough so you have easy access to the lever.
 

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Hi there,
Fiest thank you for that post, that was helpful. So I'm having a very similar problem with mine. Bought this car cheap from a dealer who got it from an auction.... can't find anything about the history of the vehicle, and clearly it's been "worked on". The hatch didn't open, so I thought it was just the handle microswitch that was bad.... unfortunately, it wasn't. I'm getting some voltage on the connector, i's a weird 5V-ish that fluctuates a little bit. See video here for tests:


I really don't get it... what I did:

  • checked all wires that I could track and nothing is broken in the boot (white-orange, purple and black).
  • checked the fuse box in the engine compartment and the rear window defroster relay is surprisingly missing!! Strange but unrelated.
  • checked the ground in the rear left panel, it's clean.
  • whatever this strange 5+V voltage is, it's powering on my plate lights just fine
  • it sounds like there is just no signal going to the latch solenoid. I tested it direct on the battery and it works fine
  • is there a relay to drive the hatch latch? I looked at the fuse box details and nothing seems to indicate this....
Any idea? I'm at a loss here....

Could be a bad BCM..... ?!
 

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Over the summer, I encountered the all too common problem that we've been having with the rear hatch not functioning. After doing a whole lot of digging, the only info I could find was about the wires splitting in the rubber sheath. Great! Now I can get started and have everything fixed in a day.

Here is what I found View attachment 93129

Not too bad. No broken wires just a little water was found in that ?drain tube?; that must be the main issue: moisture causing contact. I sealed everything up and put the hatch back together. BOOM! FIXED!....or so I thought.

A while later, with a few damp days and the car sitting for a week unused, we're back to square one. Well, square -1 because now there is absolutely no function at all....the trunk shall remain closed forever. NOPE! With the help of actually reading a youtube comment, I actually found the release lever. 30 minutes later and everything was fixed. Its super easy, so the steps and pics are below.

This is only a guide if your exterior release button is not functioning but your wiring harness is intact....here we go.

1: GET YOUR HATCH OPEN
Pull off the interior panel. and look for this little bugger:
View attachment 93137
See that tiny metal lever at bottom dead centre? That is you manual trunk release. Brilliant spot in my opinion. Push this down with a screw driver and open your hatch. Tie a string to this and hang it out the hatch every time you close it. fixed.

Kidding of course.

2: TEST THE CIRCUIT FOR FUNCTION.
With your hatch open, close the catch with your finger and unplug the wire harness from the hatch release here:
View attachment 93145
Then, look at the end of the harness like an idiot for a few minutes while trying to remember what you did with you jumper wire; like this:
View attachment 93153
This is the important bit; hold it like that. Exactly like that. If you don't, then the magical electrician in you brain will get upset and take a coffee break. Got it? OK. The left terminal is for the license plate lights and not important at all. The right terminal should be a black wire, and the middle terminal is the lead for the hatch release actuator. Shove your paperclip in those 2 holes( I know you're going to use a paper clip). If your magical electrician is not on break, you should hear little buzz-click sound. look at the catch, is it open? Good, now close the catch again and play with this a few times(its a neat sound). You've also just discovered where your problem is.

3. REMOVE THE SWITCH
Remove the 4 nuts that you saw in the first picture of step 2(they might only be finger tight, as mine were), then while holding the chrome exterior piece(switch assembly), pinch the black pinchy thing in the middle. Done. Now, Step 4.

4. Look at how dirty the back and bottom of the switch assembly are and say "f#$ing gross" before you clean it all up. While doing that, have a look at the connector; it should be super dirty too, and maybe a little corroded.

5. CLEAN YOUR CONTACTS
Scratch the contacts clean with what ever is handy and, gently, bend them down, or up, about 1/2mm. I did this because, as you may notice, the male terminals are a lot smaller than the female terminals(Oops. I guess Italian designers like to have art imitate life). Plug the wiring harness in and push the button.....buzz-click? If it made the noise, you are all done; If it didn't, you'll have to investigate further.

6. INVESTIGATE FURTHER
I don't know. I didn't have to. Please, if you did have to post your steps.
Thank you. I have been having an issue with my trunk lately. I park facing up hill the trunk will not open but I park facing down hill and poof it opens. I was starting to think it was a safety thing. Now guess I’m digging into my wiring before it gets worse
 

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I'm confused about the paper clip. So i'm making a circuit by putting one end of the paper clip in one of the slots and the other end of the paper clip in the other? There is evidence this connector has been worked on in the past. (car is used) and is damaged. Is there anywhere I can buy just the plastic piece connector?
 

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Any idea? I'm at a loss here....
Did you ever find the problem? I'm having the SAME issue presently. Getting constant 5V or 12V through the same connector, and my latch won't activate. Switch is fine, latch is fine (did the same battery test that you did). Checked all the wires I could access - they look fine. With constant voltage at the connector, you'd think the latch mechanism would be constantly activating, but nothing happens. "At a loss" as well......
 

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I had intermittent problems with my '13 Abarth's rear hatch, and then suddenly function stopped completely. I hoped this would be the fix, but no such luck. After a bunch of taking things apart, I discovered that my release button itself had failed, AT THE SAME TIME as something else - and I still don't know what the other something is. I (somewhat) carefully dismantled the trunk handle/button assembly as much as I could because I didn't want to buy a replacement (if I broke it I'd have to anyway, so no harm in trying).

I knew something in my button assembly was wrong, because you should be able to get a clean continuity test from the two relevant wires on the assembly's wiring harness connector - no "beep" from your meter, then a "beep" when you press the button. It eventually came down to continuity testing between the contacts underneath the switch itself, and where the wires came in to meet the switch assembly. Somehow in the centimeter of non-moving wire within the assembly, there was a break in the line. In the image below, the yellow slash is where continuity was lost. (Yeah, I know, there's a big bar section of wire on the left - that was me AFTER opening things up, I was sick of my alligator test leads not having contact...I fixed it later.)
108807


I decided to snip the wire that was losing contact, and re-route it through a different part in the base of the switch assembly. I'm awful at soldering, but with my Dremel and drill bits, I was able to carve a big chunk out of the bottom of the assembly and drilled an access hole to give me a good hook on the internal contact with my newly snipped wire. Once I had a solder joint I was happy ENOUGH with, I just filled the rest of the space with hot glue to help it stay still, absorb vibration, and insulate a little more.
108808

108809


Ugly as anything, but it at least delayed a $140 new handle purchase for a while.

After all this, I confirmed my latch itself was still working by pulling it out and using the alligator leads to hook it up to a 9v battery. Middle pin to battery negative, another lead on the "top" pin (where Violet would be going) and touch the other end of that lead to the battery positive - it will run the latch as many times as I want. And it is a neat sound.

So my button completes the circuit, which should be providing ground to the latch (if I understand the theory properly) and my latch is functional. What I can't figure out still, is why my Violet wire doesn't have 12v on it. From the wiring diagram it looks like it should (to me) and from my testing with the 9v battery it seems like that should be where power comes in, and waits for the button to provide ground to the latch, triggering it to open. But nothing gets it to work. All my wiring in the flexible loom at the trunk hinge is fine. I have continuity with every wire I test all the way up to the Body Control Module (C5 and C3) in the driver's footwell.

This has stumped my dad (over the phone) my father in law (in person), both of whom have fixed their own cars for years and understand this stuff, as well as myself, who pretty much thinks electricity is magic.

At this point I've given up trying to get it to work properly, and am trying to figure out another wire I can pull 9 to 12v from in the trunk lid (other than the wiper motor...I don't want to have to have my wiper on to open the back) and then I'd just jump a ground directly from the button "out" (White/Orange) to the latch middle pin. Not having great luck with that either - the latch's White/Gray ajar sensor DID have like 10v, but now only has 6...hmmmmmmmmmm

This car drives me nuts. I've had it 11 months and it's been broken in one way or another all of that except for maybe 2 weeks. Also dealing with a intermittent misfire, intermittent turbo issue, had to fix my passenger seat recline cable, driver door handle twice, that no-start issue that so many people seem to have, etc. Oh, and it blew a transmission seal and the transmission ate itself, had to get a new (to me) one in. When it runs right though...pretty darn fun to drive.
 

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When my rear hatch stopped working it was due to a frayed wire inside the rubber boot where the harness exits the body and enters the hatch.
 

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When my rear hatch stopped working it was due to a frayed wire inside the rubber boot where the harness exits the body and enters the hatch.
I was hoping that was my problem, but I checked thoroughly and everything was in great shape in there.

For a "make it work until I feel like messing with it again" solution, I wired up a 9v battery with a switch in the cab to work as a lock, so the trunk button works as intended.
 

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Keep in mind that the wires that go from the body to the hatch can 'look' fine but actually be broken inside. A "visual" inspection is not an end all, though definitely a good thing to start. I have fixed broken harnesses that upon visual inspection looked fine but where not.
 

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Over the summer, I encountered the all too common problem that we've been having with the rear hatch not functioning. After doing a whole lot of digging, the only info I could find was about the wires splitting in the rubber sheath. Great! Now I can get started and have everything fixed in a day.

Here is what I found View attachment 93129

Not too bad. No broken wires just a little water was found in that ?drain tube?; that must be the main issue: moisture causing contact. I sealed everything up and put the hatch back together. BOOM! FIXED!....or so I thought.

A while later, with a few damp days and the car sitting for a week unused, we're back to square one. Well, square -1 because now there is absolutely no function at all....the trunk shall remain closed forever. NOPE! With the help of actually reading a youtube comment, I actually found the release lever. 30 minutes later and everything was fixed. Its super easy, so the steps and pics are below.

This is only a guide if your exterior release button is not functioning but your wiring harness is intact....here we go.

1: GET YOUR HATCH OPEN
Pull off the interior panel. and look for this little bugger:
View attachment 93137
See that tiny metal lever at bottom dead centre? That is you manual trunk release. Brilliant spot in my opinion. Push this down with a screw driver and open your hatch. Tie a string to this and hang it out the hatch every time you close it. fixed.

Kidding of course.

2: TEST THE CIRCUIT FOR FUNCTION.
With your hatch open, close the catch with your finger and unplug the wire harness from the hatch release here:
View attachment 93145
Then, look at the end of the harness like an idiot for a few minutes while trying to remember what you did with you jumper wire; like this:
View attachment 93153
This is the important bit; hold it like that. Exactly like that. If you don't, then the magical electrician in you brain will get upset and take a coffee break. Got it? OK. The left terminal is for the license plate lights and not important at all. The right terminal should be a black wire, and the middle terminal is the lead for the hatch release actuator. Shove your paperclip in those 2 holes( I know you're going to use a paper clip). If your magical electrician is not on break, you should hear little buzz-click sound. look at the catch, is it open? Good, now close the catch again and play with this a few times(its a neat sound). You've also just discovered where your problem is.

3. REMOVE THE SWITCH
Remove the 4 nuts that you saw in the first picture of step 2(they might only be finger tight, as mine were), then while holding the chrome exterior piece(switch assembly), pinch the black pinchy thing in the middle. Done. Now, Step 4.

4. Look at how dirty the back and bottom of the switch assembly are and say "f#$ing gross" before you clean it all up. While doing that, have a look at the connector; it should be super dirty too, and maybe a little corroded.

5. CLEAN YOUR CONTACTS
Scratch the contacts clean with what ever is handy and, gently, bend them down, or up, about 1/2mm. I did this because, as you may notice, the male terminals are a lot smaller than the female terminals(Oops. I guess Italian designers like to have art imitate life). Plug the wiring harness in and push the button.....buzz-click? If it made the noise, you are all done; If it didn't, you'll have to investigate further.

6. INVESTIGATE FURTHER
I don't know. I didn't have to. Please, if you did have to post your steps.
 

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I've followed your steps but the paperclip between center (with/orange and bblack (ground) did not work on my fiat 500 Abarth 2012. it took me almost a year and I finlly found the problem.

I found this genius Al1Elec on this formum: https://www.cargurus.com/Cars/Discus...39181_ds555650.

I had tryed everything, following wires to BCm, take apart BCm to spot problems, check all fuses... it finally was a corroded switch.
the switch needs to have 1.5kOhms for the BCm to recognize it and send the 12v to the latch. It is a safety thing so that if the is a short during an accindent the hatch does not open by itself.

And this end my adventure with the hatch.. I cannot thank this guy enough and you too PAZZO.

Gianluigi
 

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Thank you for giving everyone an update!
 
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