Hi. Ive got a 2009 plate S-Max. Last week whilst on holiday we began having issues with the boot not opening unless the ignition was turned, then getting a “luggage compartment open” warning flashing up whilst braking even though it was most definitely closed. The interior lights also flash on. This worsened when the headlights were on as the parking sensors began singing almost constantly alongside the open boot warning. On top of this, the reverse bulbs are now very dim and even dimmer with the headlights turned on. I’ve bought a new boot latch and replaced it and the issues persist. I’m at my wits end and need advice please. 

The S-Max is known for having problems with the tailgate wiring. It seems the harness between the body and the tailgate that runs through a flexible rubber conduit is on a number of vehicles very tight. This causes breaks in the wires, and/or short circuits.

You need to unclip the rubber conduits from the tailgate and check for wiring damage. It's usually the left hand conduit that has the most problems.

 

3 hours ago, unofix said:

The S-Max is known for having problems with the tailgate wiring. It seems the harness between the body and the tailgate that runs through a flexible rubber conduit is on a number of vehicles very tight. This causes breaks in the wires, and/or short circuits.

You need to unclip the rubber conduits from the tailgate and check for wiring damage. It's usually the left hand conduit that has the most problems.

 

Thank you for responding. Absolutely correct! 2 completely severed wires and a few looking very fragile. All repaired and issues solved! 

On 4/27/2025 at 10:47 PM, Danorak said:

So, a realisation after my last few posts. Turns out, what I thought was a wiring loom feeding the lights on the right side of the hatch, was actually the rubber hose, wrapped in cloth tape, that feeds the rear washer jet. I thought the wires were inside the rubber shroud, which is what was putting me off the repair as it made it feel much more involved…

With this new realisation, I popped the grommet off the left hand side as I now realised that all of those wires probably wouldn’t be wrapped in a rubber shroud. Lo-and-behold, there was a mass of ripped cloth tape, badly applied black electrical tape, and a series of previous bodged repairs. I don’t have any before pictures, but after I’d removed all the old electrical tape and cleaned up to see what I was up against, it looked like this…

Some one has been there before and ‘repaired’ it badly. I know some will be from movement, but it looks like someone had previously cut into, I presume the cloth tape, and cut about 9 of the other wires in the process.  One wire was completely severed. Stripped the ends, couple of spade connectors, and voila…

All the other wires have now had the exposed parts insulated, the spade connector has been taped up, and all lights are working. Now I know what I’m up against, I can prep lengths of wire this week ready for the weekend. I think I remember counting 19 wires there-and they are all very taught, so I think I’m going to prepare 19 strips of wire, all about 5” in length, pre-solder the ends and cut each cable where the cuts are and solder the extra lengths in. Will give it a little more freedom of movement in the future, and peace of mind knowing that they’ve all been done. Bit more time consuming but worth it in the long run I think. 

What struck me was that we got this car when it was 4 years old, so that wiring fail happened in that first 4 years-which I think is pretty poor. Either way, I now get the chance to put it right!