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Ford Owners Club - Ford Forums > Ford Models > Ford Mondeo Club

i have a problem on ford mondeo 2009 mk4 titanium x 5dr hatch on a return journey i noticed when i pressed the breaks my dash was displaying my luggage compartment was open, on closer inspection i noticed all the rear lights were dimming when the break was pressed and the boot lid was shut tight

i did notice that the left hand break light bulb had blown so replaced bulb at a garage on way home but that did not sort my problem out.

the break lights are dimming all rear end lights inc number plate light etc and still getting luggage compartment open when pressing the break peddle,

normally i would say bad earth....? but ive removed both bulb holders away from the loom to the rear light clusters on body

but ive noticed its even dimming the boot interior light when the bulb holders are removed from both sides and the break pressed

which then points me to the tail gate center stop light..?

ive removed the plastic cover to the tail gate but can not see any water any where causing the problem

just wondered if anyone could point me where to look next

i can only think its a break in the boot lid wiring at the moment but wanted to ask before going any further

i did notice if this helps, that if the lights are off, the luggage compartment did not beep and display as oftern on dash

thanks in advance for any help




Check the main earth points (next to battery in bonnet, behind the boot trim panels, and also under the hatch panel looking at the catch system itself.


Check that these points are secure, rust free, and making a clean contact, and are not being shorted, as I suspect this may be the alternative to a bad earth...


no these earth point appear to be clean and tight

i am now awaiting a family memeber to return home so i can get inside the boot while they press the break peddle to get multi meter in there

eveything at the front end seems fine when breaks are pressed and lights on



sounds like an electrical short in the wiring loom for the boot area. If its affecting both sides, it will be up towards the roof lining before the wiring splits off, but as all earth points are clean, then this is where my money is.


I’ve sorted it well ... lol cured the problem

While in the boot I’ve noticed a noise buzzing coming from the boot latch when the
fault occurred

in the end I put a new earth to n/s rear light as this seemed to be affected
worse if no lights were on the indicator bulb light up but o/s was fine

And low and behold this cured the all problems / faults

Now I either need to find earth to that side or leave the tempre earth on permanently
any ideas where it picks the earth up from on the n/s/r loom in the boot not the hatch?

also thanks for your time & help




Hi Darren,


Not sure for certain where it picks it up, I know there is a chassis earth point on the metal panel of the boot behind the plastic interior panels. You should be able to use this, or if this is affected, you could look to remove it, sand it and clear it up then reattach the earth point?


that is where i picked up the tempre earth from to test it

i just poped in the house to see if you had replied just incase earth was close by

i am just going to cut in to the loom and solder this new earth in other wise it ilooks like i need to remove all the panels to trace it back and its not really worth it

as long as it cures my fault it will be permanent fix now

thanks again for your time and help



Glad to be of some service Darren :)


Feel free to pick the best post here (even if it is yours!) and click it as "mark solved" so that others in the future can see this


mark solved jeebo? wheres this? never noticed it


stooge75, do you mean where is the mark solved?

bottom right ?



see it now. only the original poster can see it lol

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