Technical Handbrake switch wiring

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Technical Handbrake switch wiring

nosmo

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I'm getting brake switch error on a scan
Live data shows main brake pedal switch is ok
Handbrake switch should not look like this though I'm thinking surely some wiring should be in place?
 

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I'm getting brake switch error on a scan
Live data shows main brake pedal switch is ok
Handbrake switch should not look like this though I'm thinking surely some wiring should be in place?
Looks like previous owner thought it was optional:(
So brake light switch live data shows when on and off correctly?
How about the brake fluid reservoir level sensor?
 
Looks like previous owner thought it was optional:(
So brake light switch live data shows when on and off correctly?
How about the brake fluid reservoir level sensor?
Brake switch 1 live data shows when pedal is pressed
Brake switch 2 status doesnt change when applying the handbrake
 
I think the switch should have a single wire which goes to ground via the switch when it is operated by the handbrake lever. I presume the switch gets the ground via the seat mounting. I remember reading that an owner with a new Ducato did not have the handbrake warning. Apparently the the two plastic tabs above the spade connector should have been cut off to allow electrical contact when the switch is not pressed. Your switch looks broken as the spade contact is missing, presumably with the wire attached??
 

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I think the switch should have a single wire which goes to ground via the switch when it is operated by the handbrake lever. I presume the switch gets the ground via the seat mounting. I remember reading that an owner with a new Ducato did not have the handbrake warning. Apparently the the two plastic tabs above the spade connector should have been cut off to allow electrical contact when the switch is not pressed. Your switch looks broken as the spade contact is missing, presumably with the wire attached??
My handbrake warning is on all the time

The spade contact is there but bent at 90 degrees and pointing back so you cant see it in the picture
Do I just need to ground it in that case?
I can't see it making any difference if there's no other connections to it but I'll give it a go anyways.
 
My handbrake warning is on all the time

The spade contact is there but bent at 90 degrees and pointing back so you cant see it in the picture
Do I just need to ground it in that case?
I would expect to find the wire broken or chopped off hanging somewhere as normally when connected a single wire would earth via the switch when handbrake pulled on as @rayc photo shows and must be connected to the BCM /ECU .
In the old days it just put the handbrake light on to tell drivers they had not released handbrake when pulling away, some needed that, my long dead accountant with his Jag was one;)
 
Brake switch 1 live data shows when pedal is pressed
Brake switch 2 status doesnt change when applying the handbrake
Presumably "Brake switch 1" applies to the switch contacts operating the rear brake lights., however "Brake switch 2" may apply to a second pair of contacts on the same pedal operated switch. On my x244 this second pair of contacts does conect to the ECU, and again on my vehicle serves to disengage cruise control when the brake pedal is pressed.

As already stated, there should be a connection to the handbrake switch, typically a single wire operating the panel warning light by connecting to earth when the handbrake is engaged. This connection could be monitored by the BCM, but is it?
 
My handbrake warning is on all the time

The spade contact is there but bent at 90 degrees and pointing back so you cant see it in the picture
Do I just need to ground it in that case?
I can't see it making any difference if there's no other connections to it but I'll give it a go anyways.
The switch metal work is grounded by its mounting to the seat base. When the handbrake is operated it pushes on the switch and the spade terminal is grounded via the switch and I assume the the ground goes to Body control module.
Where is the wire that was originally on the switch?? If it is loose in the seat housing etc and grounded somewhere the handbrake warning would be permanently on.
 
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Yes there are 4 wires going to the brake switch but I assume only 2 are in use as the vehicle doesn't have cruise control.
I did double check and it is disabled in the vehicle config in MES

I can see no wires around the handbrake switch at all. Only a couple of spare connectors under the seat which don't even reach to the switch.

The garage did top up the brake fluid when it went for MOT he has told me so unless that's something 🤔
 
Yes there are 4 wires going to the brake switch but I assume only 2 are in use as the vehicle doesn't have cruise control.
I did double check and it is disabled in the vehicle config in MES

I can see no wires around the handbrake switch at all. Only a couple of spare connectors under the seat which don't even reach to the switch.

The garage did top up the brake fluid when it went for MOT he has told me so unless that's something 🤔
It's not just the cruise control that the extra wires affect.
I have found on many vehicles these days if you press the brake whilst other foot on accelerator the power shuts down through communication with the ECU, this used to be a useful trick if wanting to cure squealing brakes in low gear down hills it would deglaze brake pads quite well.
 
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