My plan is to put a tow bar on my wife's 2015 Ford Fiesta. To do this I need to have a permanent 12 volt supply in the boot for the bypass interface. My plan was to get a supply from the fuse box in the passenger foot well and route the cable through the car to the boot.

So I started looking at the fuses in the passenger compartment. According to the following link

Fuse Box Link

I matched the passenger compartment fuse box design to a type 2 in this link

I looked at the owners manual and went through all the fuses that are present in the car and noticed that:-

1. My wife's car has a 20 Amp fuse in location 29 of the fuse box. This according to the owners manual is for a rear power point. The above link agrees saying that it is a 20Amp rear electrical outlet. The car does not have any visible electrical outlets in the boot.

2. My wife's car also has a 20Amp fuse in location 37. This according to the owners manual is empty i.e. not used. According to the above link this is for a 20Amp aux power in luggage compartment. The car does not have any visible electrical power in the boot.

So why are these fuses in place?

Is it possible that one or both of these fuses is connected to a wire that is routed to the boot. For me that would be brilliant because I could then  use one of those to power the bypass relay and not have to route a cable through to the boot.

I have a Haynes manual, but the fuse box is completely different to what is in the car and so I think that the electric diagrams will all be wrong. Is there anywhere I can find out the electric wiring diagrams for the type 2 ford fiesta? It would help to know if one or both the wires have been routed to the boot and what there colours were so I might be able to locate them in the boot.

Any help most appreciated

Thank You

Have you tested the fuses to make sure they are live? Worth checking there is power there before you search for wires that may not be there. 

Both of these fuses have got over 12 volts on them so they are live(ignition off).

I do appreciate that this does not mean that wires are connected from them to the boot area.  But maybe as part of a generic build??  I can but hope?

I suppose another option might be to test the wiring looms going to the boot area and search for a permanent live.

Obviously a wiring diagram would be best.

I appreciate your help, thank you

On 2/19/2022 at 1:12 PM, philp1963 said:

My plan is to put a tow bar on my wife's 2015 Ford Fiesta. To do this I need to have a permanent 12 volt supply in the boot for the bypass interface. My plan was to get a supply from the fuse box in the passenger foot well and route the cable through the car to the boot.

So I started looking at the fuses in the passenger compartment. According to the following link

Fuse Box Link

I matched the passenger compartment fuse box design to a type 2 in this link

I looked at the owners manual and went through all the fuses that are present in the car and noticed that:-

1. My wife's car has a 20 Amp fuse in location 29 of the fuse box. This according to the owners manual is for a rear power point. The above link agrees saying that it is a 20Amp rear electrical outlet. The car does not have any visible electrical outlets in the boot.

2. My wife's car also has a 20Amp fuse in location 37. This according to the owners manual is empty i.e. not used. According to the above link this is for a 20Amp aux power in luggage compartment. The car does not have any visible electrical power in the boot.

So why are these fuses in place?

Is it possible that one or both of these fuses is connected to a wire that is routed to the boot. For me that would be brilliant because I could then  use one of those to power the bypass relay and not have to route a cable through to the boot.

I have a Haynes manual, but the fuse box is completely different to what is in the car and so I think that the electric diagrams will all be wrong. Is there anywhere I can find out the electric wiring diagrams for the type 2 ford fiesta? It would help to know if one or both the wires have been routed to the boot and what there colours were so I might be able to locate them in the boot.

Any help most appreciated

Thank You

Rear power in the fiesta was at back of the centre console for the rear passengers.

When you took the fuse out of 37, were both contacts (common and fused side) the fuse plugs into there?

Hi Mark.

Our Fiesta does not have any power outlet at the back of the centre console for the rear passengers.

Both contacts are present under both the fuse 29 and fuse 37.  I removed both fuses to check.

So, if I am lucky fuse 37 will be connected to a cable which goes to the luggage compartment?

Thanks

Have you removed fuse 37 to see if powers anything else.  As fuse 37 powers the double locking relay for the rear doors on rear doors without door modules on later production vehicles. So basically internal fuse in bcm. 

 

If you are looking for a permanent live then it may be easier to run a feed directly from the battery. Got an in-line switch in an accessible place and maybe even a switch, then run it under the car from front to back. If I couldn't find a wire in the boot then that's the route I would go.

Thank you for your help.

Hi Ian, I took fuse 37 out as you suggested and checked that the locks still worked on all of the doors.  They did.  I don't know what other permanent live options to check.  The radio and side lights still work.  Fuse 30 is the front cigarette lighter, which works only ignition on.  What else should I check? But thanks again for the idea.

Hi Jonro.  You are probably right, but with my focus I simply connected to the permanent live power connection which already existed in the boot. Simple.  I am not sure where I would run a cable under the car.  If no permanent live option is available to me then I was going to run a cable from the fuse box under the door plastic trims to the back of the car that way.  Its just annoying that there is no wiring diagrams available and that the Haynes 2013 to 2017 manual electric wiring diagrams does not match my wifes 2015 fiesta.  With wiring diagrams my question would probably be answered very quickly. And if the cable does exist it would save a lot of effort.

Unfortunately I dropped the fuse 29 (20 amp) when I was trying different things with the fuses.  Could not find it, so will have to get hold of another one.  This fuse is one of the chunkier ones (25-33) ones.

Thanks again for your help.

I've pm you.