Hello,

My passenger side reverse lamp suddently stopped to work (the lamp was tested good). Driver side reverse lamp works properly.

Reverse fuse was checked good. the passenger side reverse lamp holder was measured to be 0 Volts while driver side reverse lamp was lighted.

I tried to check the wiring connecting the lamp holder and did not find any wire damage.

Any suggestions? Many thanks.

Disconnect the plug that connects the rear light cluster and inspect both sides for overheating. With the plug still disconnected, find the reversing light feed and measure the volts wrt earth with reverse gear selected and ignition on. 

37 minutes ago, nicam49 said:

Disconnect the plug that connects the rear light cluster and inspect both sides for overheating. With the plug still disconnected, find the reversing light feed and measure the volts wrt earth with reverse gear selected and ignition on. 

Thanks - Nick.

I checked not overheating on the both sides of plug.

The measured volt is 0 between the reversing light feed pin and writing earth pin when the plug still disconnected, with driver side reverse light on and ignition on. 

After doing some internet searching, I am quite confused how many reversing lamps my car (ford fusion 2010 duretec) has.

Currently only driver side reversing lamp working, if my car model has only one reversing lamp, there will be no problems.

I checked the car manual but didn't find such info.

Could anyone please confirm there's One or Two reversing lamps with ford fusion 2010 UK model? Thanks 

23 minutes ago, ford2188 said:

Could anyone please confirm there's One or Two reversing lamps with ford fusion 2010 UK model? Thanks 

All Ford UK (RHD) models.

Where only one reverse light is fitted it will always be on the 'nearside' (passenger side) of the vehicle.

Where only one rear fog light is fitted it will always be on the 'offside' (drivers side) of the vehicle.

2 minutes ago, unofix said:

All Ford UK (RHD) models.

Where only one reverse light is fitted it will always be on the 'nearside' (passenger side) of the vehicle.

Where only one rear fog light is fitted it will always be on the 'offside' (drivers side) of the vehicle.

Thanks for the confirmation - unifix.

This means that my car is fitted with 2 rear reversing lights since there is rear 'offside' driver side reversing light fitted. 

I will continue digging why the rear passenger side reversing light not working: wiring check along route from the reversing light switch to reversing light holder.

Reversing light switch working since one rear reversing light working.

I take it your car does not have reversing sensors, but if so, are they working correctly ?

Do you have a towbar, with a trailer control unit, if so, Haynes shows the feed to the reversing lights through the TCU ?

Sorry ! More questions than answers !

I've got a vague recollection about the second reverse light just piggybacking the first on the Mk6 Fiesta (very similar to Fusion).  If that's the case, you can just check continuity between the two light plugs.

21 hours ago, ford2188 said:

Thanks - Nick.

I checked not overheating on the both sides of plug.

The measured volt is 0 between the reversing light feed pin and writing earth pin when the plug still disconnected, with driver side reverse light on and ignition on. 

Thanks again for the advice - Nick.

I made a mistake when measured the volts between the reverse light feed and earth pin because I got the wrong pin. The measured voltage is proper between the reverse feed pin and earth pin, thus I checked the reverse bulb holder again and found there was contact problem. I cleared the holder area using sand paper and refit the bulb, then it worked.

2 hours ago, Paulkp said:

I take it your car does not have reversing sensors, but if so, are they working correctly ?

Do you have a towbar, with a trailer control unit, if so, Haynes shows the feed to the reversing lights through the TCU ?

Sorry ! More questions than answers !

Thanks - Paul. No any problems! Any knowledge helps.

My car has reversing sensors and they are working correctly since when I reverse, I can hear warning beeping sound when close to something.

I think there is no towbar with a trailer control unit. 

Thanks again for your kind input.

2 hours ago, TomsFocus said:

I've got a vague recollection about the second reverse light just piggybacking the first on the Mk6 Fiesta (very similar to Fusion).  If that's the case, you can just check continuity between the two light plugs.

Thanks - Tom.

I will check continuity between the two light plugs if the problem comes back.

I found the problem and solved it now. It is one contact problem of the rusted bulb holder. I did measure the voltages between the pins and earth in the feed cable connector for both left and right sides to do comparisions which proving the reverse feed signal is the same to passenger and driver side.

Here is diagnosis and testing procedure (Page 89 - ...) if there is a reversing light problem for ''2002-2008 Ford Fiesta/Fusion Workshop Manual + Wiring Diagrams''. I got the website from the forum but could not find the author to quote here.

https://cardiagn.com/2005-08-ford-fiesta-st-lighting/