Fiesta 2010 - Both tail lights stop working

[species36181]

Hey all,

I've been having an issue with both my tail lights for a while.

they randomly would stop working, If I pull the fuse out F22 (the one in the engine bay) and put the same fuse back in will start working again.

I've tried changing the bulbs and the fuse.

Then after a few days It would stop working, I was on the motorway in the evening it happend, luckily It wasn't too dark and another driver flashed me.

I've taken it to a garage and he's changed the fuse as well as cleaned out the fuse box and it's happend again.

He did tell me last that if it happens again I would need to change the fuse box. 

Just wondering if anyone else has had the same issue before or anyone knows what the issue may be?

Should I take it to Ford?

Thanks.

[Luke4efc]

46 minutes ago, species36181 said:

I've taken it to a garage and he's changed the fuse as well as cleaned out the fuse box and it's happened again

If your garage has changed a fuse without actually testing if it's blown you need to find another garage.

Have you got the correct lamps installed? I've seen various wacky faults all down to someone fitting the wrong lamp.

[species36181]

19 minutes ago, Luke4efc said:

If your garage has changed a fuse without actually testing if it's blown you need to find another garage.

Have you got the correct lamps installed? I've seen various wacky faults all down to someone fitting the wrong lamp.

Thanks Luke, he's tested the fuse but he changed it anyway, I initially found out about this issue when I went to change both of them due to thinking the bulbs had blown.

I'll try fitting new bulbs during the week to see if that solves the issue.

 

~EDIT: Also forgot to mention, the break lights work fine, it's just the tail lights

Edited April 25, 2021 by species36181

[Luke4efc]

59 minutes ago, species36181 said:

he's tested the fuse but he changed it anyway

That's even worse! A fuse either works or it's blown.

[Dan62]

Difficult to understand why removing and reinserting a fuse would temporarily fix the issue.
Logically, I would go for reseating the connectors of the GEM/BCM first.
The diagram might help

Lighting.pdf

[Bobr]

34 minutes ago, Dan62 said:

Difficult to understand why removing and reinserting a fuse would temporarily fix the issue.
Logically, I would go for reseating the connectors of the GEM/BCM first.
The diagram might help

Lighting.pdf 209.1 kB · 0 downloads

Makes me think of corroded contacts.

[unofix]

On 4/25/2021 at 8:00 PM, species36181 said:

I've been having an issue with both my tail lights for a while.

Hi JD, next time both tail lights are not working can you check to see if both number plate lights are on ?

 

[species36181]

Hey guys, thanks for the replies, I'll check the number plate lights the next time it doesn't work.

Just a random guess, does anyone think it may be the Light Control Switch? as the fuse is for that?.

On another note, I noticed that they also randomly start working again if the car has been off for a while.

They stopped working on Sunday when I posted this issue and when I went to asda this morning they were working.

 

Doesn't make any sense lol

[species36181]

On 4/27/2021 at 9:59 AM, unofix said:

Hi JD, next time both tail lights are not working can you check to see if both number plate lights are on ?

 

Hey,

 

I've checked this today as they've stopped working again, both number plate lights are off.

Thanks,

[unofix]

Hi JD, so you either have a bad connection on the plug to the GEM or the actual GEM unit is faulty.

Check pins 1 and 13 on the plug if they are ok then I would say replace GEM.

Since the front lights are working the supply to the module has to be fine and also the switch sends only a signal to the GEM to turn the lights on and again the front work so the switch must be ok.

[Dan62]

3 hours ago, unofix said:

Hi JD, so you either have a bad connection on the plug to the GEM or the actual GEM unit is faulty.

Check pins 1 and 13 on the plug if they are ok then I would say replace GEM.

Since the front lights are working the supply to the module has to be fine and also the switch sends only a signal to the GEM to turn the lights on and again the front work so the switch must be ok.

You have assumed the front parking lamps / sidelights are operational but you probably wouldn't notice if you have the headlamps on.
First cheapest and easiest option would be to replace the switch.

[species36181]

16 hours ago, unofix said:

Hi JD, so you either have a bad connection on the plug to the GEM or the actual GEM unit is faulty.

Check pins 1 and 13 on the plug if they are ok then I would say replace GEM.

Since the front lights are working the supply to the module has to be fine and also the switch sends only a signal to the GEM to turn the lights on and again the front work so the switch must be ok.

Thanks Unofix, much appreciated. I'll give this a shot.

[species36181]

For anyone that comes across this issue, I've managed to resolve it in my case.

Turns out the fuse connection to the fusebox itself was a bit loose, so it wasn't always connecting. 

That's why pulling the fuse out and seating it back in would make it work for a while til it got loose again.

Thank you all for your help.