My n/s rear indicator bulb isn’t working. I have changed the bulb but no joy, I checked the bulb on the o/s rear light and it works. The contacts are clean and I bent the contact towards the bulb and it definitely makes contact.

Has anyone had a similar issue? All other lights work apart from the n/s front daytime running light so I’m not sure if it is related and could be a fuse?

19 minutes ago, Dannylfc86 said:

My n/s rear indicator bulb isn’t working. I have changed the bulb but no joy, I checked the bulb on the o/s rear light and it works. The contacts are clean and I bent the contact towards the bulb and it definitely makes contact.

Has anyone had a similar issue? All other lights work apart from the n/s front daytime running light so I’m not sure if it is related and could be a fuse?

Have you checked there is power going to the rear indicator contacts?

No, I have a multimeter so can do. Was just wondering if this is a common issue like a fuse.

5-7v going to the o/s which is working but less than 1v going to the n/s fitting which isn’t working 

Bad connection somewhere, probably the earth. Both sides should have 12 volts or more.

I’m using a multimeter so it isn’t giving a constant value, it goes up to 7v when the indicator sounds and back to 0v when it sounds, so the good side goes 7-0-7-0. The side with no light working remains under 1v

I think the indicator flash voltage is too quick for your multimeter to accurately measure.

However the lack of voltage on the failed side shows that's not getting powered anyway.  So you need to check the other end of that wire at the BCM now, the fusebox under the glovebox.  I don't know which number it'll be unfortunately.

If the flash has a 1:1 mark/space ratio a meter would read half of the supply volts ie about 7V on a car with the alternator charging.  A DVM would probably struggle to indicate this.  Using a meter with a needle would probably give a better indication.

The Fiesta/Puma heater control valve uses a variable mark/space square wave voltage to control the position, but this is at a much higher frequency than an indicator lamp (and infinitely higher than a BMW indicator!) so a reasonable meter will show the average volts.  I think the variable square wave is used to provide "dither" to the valve so it does not get stuck, a bit like a submarine depth gauge.

1 hour ago, TomsFocus said:

I think the indicator flash voltage is too quick for your multimeter to accurately measure.

However the lack of voltage on the failed side shows that's not getting powered anyway.  So you need to check the other end of that wire at the BCM now, the fusebox under the glovebox.  I don't know which number it'll be unfortunately.

Thanks, I’ll have a look at the wiring diagram and try and work out which fuse it is.

double check the other bulbs

on her 2008 mk 2.5 - it went mad in the summer and I kept finding the rear doing nothing - first round the filament had fallen off but was landing back on the post and pretending to work - (had the same on the other side 4 years back) - but a week later it was off again - but this time I either replaced the repeater or put a new one in the front and magically the rear one came to life !

 

on the other side her wing based repeater was working underwater !!!!   the whole thing was full up with the lens cover coming unbonded from the rear of the lamp unit

I plugged the car in and this fault code came up. Has any experience or the ground issue?

On 4/15/2023 at 10:17 PM, unofix said:

The ground tab in the lamp holder is not protruding far enough out and is not making contact with the side of the bulb.

It just needs eased out a few millimeters with a small screwdriver.

 

Thanks, I’ll try tomorrow and share back whether it worked or not.

i bent up the bottom tab if im being honest and not the side when i tried it so hopefully this will sort it.

Update - an Earth cable needed replacing.