Ok so.
i wanted to install some lights under my bonnet for working when its dark if need be.
i thought, great that should be easy, i will tap some LED panels into the bonnet ajar switch.
well seems its not so easy after all.

From my understanding looking at the wiring diagrams, a wire comes from the security module, into the switch, and then another wire comes from the switch to ground causing the switch to complete the circuit.
i disconnected the plug, and now when i put my test light on the plug i am getting no power at all.
my light should be completing the circuit and lighting up.
so my question is, what could be wrong in this circuit that is causing it to get no power? Relay? Fuses? All i can see from the wiring diagram is it is a direct connection to the SLCM which would indicate the module is not outputting power to this circuit.

 

The bonnet lights were not on all production #s either before or after a certain point I have not figured out which way or another

Mine ( 96 Sovereign ) does not

Researching

There must be a switch somewhere lelling the SLCM that it is open or maybe on the interior bonnet latch handle under the dash

What page # are you looking at in the 95 wiring guide

 

I do see it on a 1996 wiring guide as the hood switch

This would be pin CA19-21 on the SLCM , blue white wire

The pin should have 7.9 volts on it and you can see it on the switch as well

 

yep.
exactly what i was looking at.
and seems like it should have power coming from the SLCU.
not sure if maybe there is broken wiring somewhere or maybe it is an option that has been deprogrammed off and would need to be turned on to make the circuit live.
my understanding is this is the switch that would set the alarm off if someone opened the bonnet and prevent remote locking of the car if bonnet was open.

 

Maybe something to do with a specific Australin SLCM and a American installed

 

just got to work it out so i can decide to repair it if possible or if to disconnect the wiring and repurpose the switch for installing underbonnet lighting

 

You can have a independent of the SLCM design of your own and just pick up 12 volts from a spare fuse position

Fuse position 1 - 9 is hot at all times

and the big battery cable at the engine rear firewall

 

exactly what i was going to check the wiring for.
using the fuse box at the front of the engine bay will be perfect as less wiring to run.

 

Spud Old Mate,

My car is an English spec V12 that was privately imported so it may not be the same as an Oz spec car but I just went down to my car and measured the voltage across the pins in the plug to the bonnet switch and it was only about 1.8 Volts DC with a battery Voltage of 12.6 + so there wouldn't be enough power there to light up an underbonnet light in any case. The measurement was done with the IGN off.

You'll have to rig a separate switch and wire your lights directly to one of the terminal posts on the firewall.

Cheers,
Jeff.

 

When you flip the fuse box upside down there are 2 connectors so you can get the box out of the way and pick up a wire on the car side of the connector ( but a extra unused wire probably does not exist)

So you can use a wire dedicated to something and tap into that

an example would be unything on for fuse 1 - 9 , 11 . 13 . 15 and a couple more that are hot at all times

But in your final installation you would most likely run the wiring with the heavy battery cable which attaches from the fuse box to the firewall so end you would have to ask yourself well why did I not just use the firewall battery terminal post

 

yeah that sounds right.
just had a look in the elec manual and yeah its a 1.7v ground triggered circuit so will have to wire in a new switch. I may have one laying around.

shame. I was hoping for the super easy option.

 

I don't see the need for a relay so that simplifies that but there is a couple of relay positions on the front right for the V12 engine not used on the inline 6

You will most likely not close a relay with 1.7 volts but to do so makes for a aditional circuit

The purpose of a relay is to use a low amperage wire to control a high amperage current wire,,,,,,, in most cases

 

yeah just simplified and edited my post.

all it needs is constant power - led - trigger switch - ground.

 

Nailed it

Now about those electric no hands bonnet risers ........

 

dang.
now thats an idea

 

https://www.ebay.com.au/itm/19449845...id=21034416656

would just have to find somewhere with enough room to mount this...........

 

Thats them ; I've been eyeballing how to mount

With a switch under the side mirrors

 

Another thought, would the 'close' force of the actuator be enough to engage the bonnet/hood latches? Or could you do away with the latches altogether?
Cheers,
Jeff.
P.S. In the eBay blurb it states that there is a wireless remote option at 433 mHz.

 

i have used linear actuators just like that in other machinery applications before and they hold closed with enough force that the latches would not be required.
the one thing you would have to make sure of is that when no power exists they hold in the closed position. Just to ensure a power issue will not pop the bonnet open.
i am not ready to undertake this install atm myself, but have added it to the list of “will get to one day” jobs. Lol

 

Same on my some day list

With the actuator holding on it's own negates the need to have a bonnet latch or switch if you have a second switch to unlatch the bonnet

Fortunatly the bonnet points in the down wind direction

I dought the actuator will unwind with power off