Hello there here goes with my first topic.

Today the drivers side rear stop lamp failed to work. 
I have checked the lamp and it is fine, checked all the wiring and connections within the rear light cluster-all ok

Cleaned all the connectors in the lamp cluster- all ok
Checked the 5 amp fuse in the main fuse box-this was ok.

The nearside lamp cluster is all ok with everything working.

My question is where is the lamp supplied from? Does it go straight to the brake pedal? Is it supplied in tandem with the near side stop lamp? Where so where should I look for the broken connection.

Unfortunately i

I do not have a workshop manual, or a wiring diagram.

Has anyone come across a similar problem and found a solution?

Cheers

Lynton

 

Check the earth tab inside of the lamp holder.

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.

 

13 minutes ago, LyntonP said:

My question is where is the lamp supplied from? Does it go straight to the brake pedal?

No the brake lights are controlled and supplied from the Body Control Module (BCM). They are not directly connected to the brake light switch on the pedal.

15 minutes ago, LyntonP said:

Is it supplied in tandem with the near side stop lamp?

Yes. Both nearside and offside lamps are connected in parallel and supplied from the BCM. Note: the centre brake light is usually on it's own independent supply from the BCM.

The usual cause of failure like this, is that the ground to the lamp is missing. Check with a multimeter between the lamp holder positive, and a good known earth point.

Within the cluster the stop lamp has two wires.

Red—-Positive?

Black—Ground?

Black wires all connected from other lamps and these do go to ground.

Is this a correct assumption of mine?

Thanks for such prompt replies.

Cheers

Lynton

17 minutes ago, unofix said:

Check the earth tab inside of the lamp holder.

 

 

Hi thanks for the reply.
I did bend the earth connection out a little bit and cleaned the contact with fine emery.

I will check again after tea.

Cheers

Lynton

To be honest the colours of the wires change so much from model to model and year to year it's hard to confirm.

If the black wire is short to earth then you can assume that to be the negative.

Hi thanks for the reply.
I did bend the earth connection out a little bit and cleaned the contact with fine emery.

I will check again after tea.

Cheers

Lynton

Just got out of the garage after re wiring all the earth wires to each lamp. Also found duff reversing lamp (new lamp fitted).

Ignition on - same fault message - Stop lamp bulb failed. Pressed brake pedal and both stop lamps lit. Not the neatest job I have done (too much of a rush). May revisit it when I have a bit more time.

Many thanks to everyone for their suggestions and shared knowledge

Cheers

Lynton

Question Could the duff reversing lamp somehow cause the fault message on the dash?

No message on dash and brake light worked normally after I replaced the reversing lamp??? 
Lynton