Technical Boot light

Currently reading:
Technical Boot light

Joined
Aug 6, 2022
Messages
95
Points
122
Location
Sheffield
Hi all, I’ve a 2008/2009 Cross Multijet. When i bought the car there was no bulb in the boot light, so i popped one in there today and i still don’t have a working boot light!
I’ve read this thread https://www.fiatforum.com/guides/boot-light-installation.864/ but dont know for certain if my car would have had one from new ( i assume it did). The central locking and remote release work on the tailgate and if i leave it open and use the remote locking the doors lock and unlock indicating something isn’t shut. However unlike the main doors i do not get a dash message with the ignition on to say the tailgate is open (don’t know if it should or not) So I’m assuming that either their is a loom issue between the tailgate lock and the body of the vehicle or that there is some issue with the tailgate lock/latch or that just didn’t have alight in the first place. Any suggestions as to how i check this out before i risk ordering a new locking mechanism and potentially spend on a part i don’t need?
Thanks in Advance
 
It’s likely to be the boot lid switch

I don’t think it recognises if the hatch is open. Should remember as I have driven the car a few times with the hatch open. But I can’t and don’t have the car here

Anyhow sometimes you can get them working again by giving the boot handle a gentle bash
 
Thanks, that get’s me nearer, so is are the relevant micro switches in the lock latch or the external release? In most of my older cars if this happened it was either a separate “pin switch” or a loom break. So just want to make sure i get the right part
 
Thanks, that get’s me nearer, so is are the relevant micro switches in the lock latch or the external release? In most of my older cars if this happened it was either a separate “pin switch” or a loom break. So just want to make sure i get the right part
Yes

It’s under the lip

New cars make a nice satisfying click noise

As dirt gets thrown up it starts to jam

It’s very common to fail or to become intermittent. Whether this is your problem would require further investigation
 
Thanks Koalar, so is that part 3 on this? As on mine it has an electrical connector to it or is it the release button under part 1?
1659980209058.png
 
There's a guide to removing the boot lid handle here:

I cleaned mine and put it back, which solved the issue I was having (boot lid opening itself) due to muck around the handle micro switch.

No idea if this will help your issue, but worth doing anyway.

My door warning light on the dash is definitely on if the boot isn't shut properly.

So presumably there's a switch connected to the latch that illuminates the warning light and boot light when the boot is open?
 

Attachments

  • 07a_locationPlug.jpg
    07a_locationPlug.jpg
    163 KB · Views: 42
There's a guide to removing the boot lid handle here:

I cleaned mine and put it back, which solved the issue I was having (boot lid opening itself) due to muck around the handle micro switch.

No idea if this will help your issue, but worth doing anyway.

My door warning light on the dash is definitely on if the boot isn't shut properly.

So presumably there's a switch connected to the latch that illuminates the warning light and boot light when the boot is open?
Correct

there is an electrical connection in there

Even though they look the same from the outside

The active (no remote) and dynamic (with remote) are a different part

When I changed my dynamic hatch for one from an active I had to change every single part over otherwise when you lock the doors they would pop back open.

I tried to use as much of the active hatch as possible as it was newer in the end everything needed swapping over.
 
So presumably there's a switch connected to the latch that illuminates the warning light and boot light when the boot is open?
I just checked this on my car by closing the boot latch (with a tent peg!) with the boot lid open, ignition on and all other doors closed.

There are two switches in the latch mechanism.

I can hear the first switch click as soon as the latch is moved. This turns off the boot light.

The second switch is activated when the latch is fully closed. This turns off the dash door warning.

From OP's symptoms (no boot light, no dash warning light), I would think it's the switches or wiring from the latch (part 3 in the diagram)

I guess OP's car would have had a boot light from new? As I understand, posh models had a boot light, most (eg Dynamic) had wiring but no light fitted, base model Actives don't have the wiring for a boot light.

I would start by cleaning the handle and checking the latch wiring inside the boot lid.
 
Last edited:
I just checked this on my car my closing the boot latch (with a tent peg!) with the boot lid open, ignition on and all other doors closed.

There are two switches in the latch mechanism.

I can hear the first switch click as soon as the latch is moved. This turns off the boot light.

The second switch is activated when the latch is fully closed. This turns off the dash door warning.

From OP's symptoms, I would think it's the switches or wiring from the latch (part 3 in the diagram)

I would start by cleaning the handle and checking the latch wiring inside the boot lid.
Well done that man for testing in real life

Looks like I got it wrong
 
Thanks all, checked over the release button and it's free and working correctly so it looks like it's the microswitches in the latch or the wiring to them that's not working. I've also tested the latch with a large screwdriver similar size to the striker plate and no boot light or warning on the dash. I flooded the latch with switch cleaner and left it overnight to see if the old lubricant was gumming it up. I knew the car had basically stood for a couple of years before being recommissioned in February by it's last owner, so thought it would be worth a try.
Anyway nothing has changed. A quick chat to our local dealer and they’ve identified that there was an updated part listed for my car so I need to check the part number of what’s already fitted. Apparently if I’ve the older latch, it’s not just a replacement latch but a new loom too 🤦🏼‍♂️. Whilst I like to have everything working I think the cost may be prohibitive 😳
 
Thanks all, checked over the release button and it's free and working correctly so it looks like it'st the microswitches in the latch or the wiring to them that's not working. I've also tested the latch with a large screwdriver similar size to the striker plate and no boot light or warning on the dash. I flooded the latch with switch cleaner and left it overnight to see if the old lubricant was gumming it up. I knew the car had basically stood for a couple of years before being recommissioned in February by it's last owner, so thought it would be worth a try.
Anyway nothing has changed. A quick chat to our local dealer and they’ve identified that there was an updated part listed for my car so I need to check the part number of what’s already fitted. Apparently if I’ve the older latch, it’s not just a replacement latch but a new loom too 🤦🏼‍♂️. Whilst I like to have everything working I think the cost may be prohibitive 😳
I get one from the breakers

Any from a similar year should work as long as it not from an active.

wiring is a pain there’s no break in harness.

When I changed my hatch I had to thread the old wire back into it. I followed the loom forward as far as in front of the rear seats and there is no join

Before then I will double check the wiring hopefully it will not be too different from the dynamic
 
Great

12 Volts are permanently connected to the bulb

And the path to ground is completed when the switch operates

Do you have a multi meter, volt meter or test lamp
 
Yes there’s 12v to the light but as others have mentioned I’m assuming this needs a load on it. I have access to a multimeter but am not that familiar with some of the wiring in the car yet
 
You should have with the bulb installed

12v going into the socket red and green

And

12v coming out of the socket
Orange and white

And

12 volt going into to the boot latch switch which is the other end of the orange and white

Just test the orange and white with a bulb installed at the boot latch first if it’s there you can assume everything else is fine

That measuring with the black lead of your multi meter on chassis ground somewhere a bolt screw that touches bear metal will do
 
Last edited:
You should have with the bulb installed

12v going into the socket red and green

And

12v coming out of the socket
Orange and white

And

12 volt going into to the boot latch switch which is the other end of the orange and white

Just test the orange and white with a bulb installed at the boot latch first if it’s there you can assume everything else is fine

That measuring with the black lead of your multi meter on chassis ground somewhere a bolt screw that touches bear metal will do
Thanks, that confirms it. There’s a good 12v there when I do that. So looks like I’m chasing a working latch. Thank you that’s been really helpful 👌🏻👍🏻
 
Just need to check that the back and green cable doesn’t have a break and a clean path to earth

With the multi meter set to ohms the black and green cable from the latch should 0 ohms to the chassis body

It’s more than likely just the switch.

But we do have a fair few problems with the earth return in the rear light clusters
 
Back
Top