Remote Boot Release

I can see that this subject has been covered somewhat on here but one detail seems to be missing.

Sometime in the medium future, I will send my SCU to Paul at Technozen for some fob work and replacing the relays (precautionary).
At the same time, I will ask him to activate the boot release signal and add the additional pin connector for the signal out.
This will go to a relay.

Ideally, I would like to take the boot release solenoid power from after the handbrake switch (in order that the boot release can only be effected when the handbrake is on) but that signal-out seems to be integral to the handbrake switch. Shown in the attached file. What have others done? 

And does anyone know the meaning of "header" which is all over the circuit diagrams in the manual.
Thanks.

 

Header is white plastic block protecting several wires connected together.

That makes sense. Thank you.

I like the idea of interlocking the handbrake light with the remote fob, however the small bit of the circuit shown is on the earthy side of the circuit. You need to pick up the live side & the easiest way to achieve your ends is to use a relay in parallel with the warning light.
At one time modifications such as this was part of my “revenue stream” & so I’m familiar with the comings & goings of the cars wiring. The instrument cluster derived power via fuse 1 & SK1 joint & the HB lamp illuminates when the HB switch links to ground/ frame/chassis as per your picture.
I would be inclined to use a small single pole relay across these to then enable whatever else you wish to add.
M

  I’ll add this to illustrate the type of relay I use, the battery is included to indicate scale. 
The relay mounted on the PCB is prepared to install in a job later, by doing it this way you increase the ruggedness of the assembly as well as giving your soldering iron a better look at the opposition. 
M

Apologies, AP.. we are currently in France with the TF. Behaving itself impecably on foreign roads.
My longest run in it yet and finally passed the overall confidence test.

Back to the remote release, I absolutely bow to your practical experience but I do not see how the relay will only work if the handbrake light is on if the live is taken from the warning light branch.
For the current to be "on", the handbrake switch needs to be on and that is basically touching the circuit to earth (as you pointed out).

If I take the live feed for the relay from the warning light feed, then I will be able to operate the remote as long as the ignition is on (as the hb warning light will not come on without ignition position live) and not only when the handbrake is applied. Without opening up the hb switch, I guess I will not be able to do what I want.

Very interested in your nano-relay and board. Will reasearch that.
I see that Mr A. Mazon has delivered a strip of 1.2mm stainless on which I will mount the solenoid. Pictures when the project starts in case of any interest.

Righto, fair point, let’s take a feed from elsewhere & stick a diode in the circuit. I’m up to the short & curlies at the moment, I’ll have a look at the diagram later.
M

If you want a system to engage when the HB is on, irrespective of the state of the ignition, you could achieve that by wiring the relay between a constant live & the black/white wire running from K109 to the brake switch. (C0288 to C0091). You would also require a diode wired in circuit. This would be introduced by cutting wire (C0288 to C0091) at the header K109 end, a 1N4004 diode would be fine & the silver bar end would connect to the cut wire & the plain black to the header. I hope this helps, anything more complex would introduce logic
M

Thanks again AP. I will work on your suggestion.
Back from France now and part 1 of the project is complete. Photo attached.
 

This will be bolted on the the boot lock support bracket (photo to come).
Then I have to wait for funds to get the ECU sorted for the boot release signal.

Packaging the actuator neatly out of the way can be a challenge if you run, as you just have, with a full boot. The actuator can pull & push, depending on the way around you mount it, I’ve had mine oriented in the push configuration & find that by mounting it behind the lock plate you can keep it out of the way. Others have experimented with this arrangement & have found it problematic. Mine however has performed faultless.
M