Technical one reverse light not working

[arekp]

As you can see, the driver side reverse light isn't turning on.
The bulb is fine.
There's no CEL.
The rest of the lights on driver side taillight cluster work fine.

The passenger taillight cluster is fine.

Using a multimeter, looks like the driver side reverse wire (grey/green) does not get activated when reverse gear is selected.

Any suggestions where I should hunt next would be welcome!

Also, surprising that Blue on driver side isn't reading a perfect 0V. I'm consistently getting 0.03V.
Could this be due to my neutral wire repair job?

These codes are imprinted on the taillight , what do they mean?

 

[AnthonyH]

As you can see, the driver side reverse light isn't turning on.
The bulb is fine.
There's no CEL.
The rest of the lights on driver side taillight cluster work fine.

The passenger taillight cluster is fine.

What do you mean by CEL?

View attachment 451580

Using a multimeter, looks like the driver side reverse wire (grey/green) does not get activated when reverse gear is selected.
View attachment 451582

This connection plug is the likely problem. The contacts inside will be faulty , broken or rusted.

View attachment 451581

Any suggestions where I should hunt next would be welcome!

Also, surprising that Blue on driver side isn't reading a perfect 0V. I'm consistently getting 0.03V.
Could this be due to my neutral wire repair job?

Ignore the 0.03V, it's just background reading error

These codes are imprinted on the taillight , what do they mean?
View attachment 451583

 

[arekp]

What do you mean by CEL?



This connection plug is the likely problem. The contacts inside will be faulty , broken or rusted.



Ignore the 0.03V, it's just background reading error

Check Engine Light

The connector is fine (except for the earth). There is no rust. All pins are shiny. Just no power getting to the reverse light wire....

 

[simon_16vpunto]

The 500x only has one reverse light.

The other side is a fog light.
Well at least it was on my uk spec 500x

 

[AnthonyH]

My fiat also has only one reverse light.

 

[arekp]

Thanks all. Mystery solved.
Just tested it and: Fog light after all!

 

[s130]

My reversing light whilst lighting up would not work for me. I replaced the P21W bulb with a 500 Lumens LED Bulb.

Much brighter and legal in the UK for a reversing light. No more scraped or dented bumpers anymore.

The design of the reversing (and fog) light is really stupid IMHO. If you bend down and look the bulb is actually located above the lens and the reflector is limited in size / upper coverage so a lot of the 360 degree bulb output is wasted.