Hi folks. Nice to join up.

Can anyone confirm if the high level brake light is only illumated during braking or if it's supposed to be on with rear tail lights? 

RIght now, I switch on lights and it comes on, but gets brighter with brake pedal applied (same as tail lights basically). 

I'm think it's got a fault but maybe someone can confurm their one does.
 

Thanks in advance.

Hi,

That is faulty.  The high level light should only be on when braking.

8 minutes ago, TomsFocus said:

Hi,

That is faulty.  The high level light should only be on when braking.

Cheers for that. Confirms what I thought. 

Common issues to cause this? Brake pedal sensor or dodgy wiring?

47 minutes ago, Fordy_1903 said:

Common issues to cause this? Brake pedal sensor or dodgy wiring?

The centre high level brake light is controlled by the Body Control Module (BCM) so you can rule out anything to do with the brake pedal switch.

Assuming that this issue has only just happened, and not that it has been like this the whole time you've owned the car, the likely issue is water ingress to the BCM connectors.

4 minutes ago, unofix said:

The centre high level brake light is controlled by the Body Control Module (BCM) so you can rule out anything to do with the brake pedal switch.

Assuming that this issue has only just happened, and not that it has been like this the whole time you've owned the car, the likely issue is water ingress to the BCM connectors.

Thank you my friend. Yes, I presumed that because the brake light is working fine and the light isn't on until tail lights are switched on, then it's more likely electrics than sensor. 

Where is the BCM located for me to check?

1 minute ago, Fordy_1903 said:

Where is the BCM located for me to check?

The Body Control Module is part of the passenger compartment fusebox. The BCM and fusebox are fully integrated and are considered by Ford to be an unserviceable unit.

6 minutes ago, unofix said:

The Body Control Module is part of the passenger compartment fusebox. The BCM and fusebox are fully integrated and are considered by Ford to be an unserviceable unit.

Ah shoot. So to fix a ***** tail light (not even an essential one at that), I'd need a potential BCM replacement?

6 minutes ago, Fordy_1903 said:

I'd need a potential BCM replacement?

Possibly, but you need to do some checking of the connectors before you jump in to replacing parts.

Has this problem only started recently ?

1 minute ago, unofix said:

Possibly, but you need to do some checking of the connectors before you jump in to replacing parts.

Has this problem only started recently ?

Hard to tell.... my wife noticed it coming on and off when my son was driving, so I presume only just started.

Wiring into back of the light housing or from the fuse box?

If this is something that it has only recently started then my thoughts would be to check the connectors of the BCM.

There are only two wires connected to the high level brake light. (a) a ground wire (b) the live supply when the brake light should be on.

If you are getting a dim, or reduced brightness light when the tail lights are on then the supply must be coming from the BCM.

6 minutes ago, unofix said:

If this is something that it has only recently started the my thoughts would be to check the connectors of the BCM.

There are only two wires connected to the high level brake light. (a) a ground wire (b) the live supply when the brake light should be on.

If you are getting a dim, or reduced brightness light when the tail lights are on then the supply must be coming from the BCM.

Yes, a dim light.

Where exactly am I checking the connector on the BCM? Is it to fuse?

The BCM has usually 3 or 4 large multi-way connectors.

You need to unplug them and look for signs of greenish corrosion of the pins, and/or signs of water ingress.

8 minutes ago, unofix said:

The BCM has usually 3 or 4 large multi-way connectors.

You need to unplug them and look for signs of greenish corrosion of the pins, and/or signs of water ingress.

Right you are boss.... I'll check them over tomorrow. Cheers for your help. Much appreciated.

21 hours ago, Fordy_1903 said:

Right you are boss.... I'll check them over tomorrow. Cheers for your help. Much appreciated.

I checked the passenger and engine compartment fuses - nothing looked untoward. Removed/reseated some connector on BCM. Nothing made a difference. Eventually (temp fix) just disconnected the high level brake light.

You haven't by any chance fitted led bulbs, I had this problem years ago with a nissan primera, cheap bulbs from Ebay I found that the high level brake light was on with sidelights. Brought decent bulbs problem solved.

3 hours ago, Treef said:

You haven't by any chance fitted led bulbs, I had this problem years ago with a nissan primera, cheap bulbs from Ebay I found that the high level brake light was on with sidelights. Brought decent bulbs problem solved.

Haven't touched the bulbs. We bought car about 3 months ago and as far as I'm aware, was working ok. It could be worth replacing with new bulbs though.