951Dreams

(Yeah, I know just bypassing the factory alarm all together and replacing it with an aftermarket alarm system would be easier. Just humor me)

So, I'm wanting to do keyless entry with trunk pop. Simple enough. I can do that. But it gets more complicated. Here's where I need better minds than mine to help. And someone who understands the factory alarm wiring.

I want to make a circuit that interfaces with the factory alarm key tumbler. In effect, I want the alarm ON if the doors are locked by the keyless entry, and off if it's unlocked by the keyless entry. Also, I want the OFF position on the tumbler to ALWAYS have the alarm off. So, in effect, tumbler in alarm ON position, it's controlled by the keyless entry. Tumbler OFF, it's just plain off no mater what the keyless entry is doing.

I get I'll have to make a separate circuit for that with switches, because I don't want the central locking to be controlling it too. I guess I could use a diode to keep the central locking from feeding into the circuit, then put the controls for the alarm upstream of the diode...??

It gets more complicated, I would also need to isolate the circuit when the ignition is on. So the alarm can't be turned on accidentally while the car is running. So this new switch would need to be cut off from the keyless while running. That honestly should be easy enough. Just cut the power to the alarm switch(my new one) while ignition is on.

Lastly, I need to better understand how the alarm tumbler works. I'm not finding the info I need. I know if the tumbler is removed, it defaults to alarm on. (or does it just disable the starter, I'm unclear from the post I've read) But I'm not sure how it's doing this. It's just two wires, so there should only be on, and off. But this doesn't seem to be the case. I've read that shorting the wires together turns the alarm ON. But making them "OPEN" (removing the switch) ALSO turns it ON. So how does it have 3 modes? ON, OFF, and removed??? The removed and shorted together modes seem to be mutually exclusive!?!?

So, I'm thinking a remote switch, that's upstream and isolated from the central locking, controlled by the keyless, that turns the alarm off and on. Also another switch(s) that's turns the inputs off from the keyless while the ignition is on (just for safety). Plus, I've got to figure out how to work it if I want it to lock and unlock with the ignition. But I don't think I want that feature on anyways. Seems like "lock your keys in the car" central. Ask me how I know that.... Might do a delay switch that disables the keyless control of the alarm switch like a few seconds after the ignition is turned on/off. Hmmmm.....

The parts I'm unclear about is how to achieve what I'm wanting between the alarm tumbler and the alarm, since I can't seem to get my head around how it's working. And also, how to bypass the whole thing if the key is in "alarm off". So any idea's?

Yeah, this is complicated, and more work than it's worth. But I just got a new soldering gun, and itching to use it! LOL Really, I think it would be fun to figure this out. So any input is welcome.

There are some systems that have a module to do all this you can buy pre-made for their keyless units. The 944 isn't one of them.

thomasmryan

If you are a MAC/iDevice user, the RFdrino has potential to do whatever you want to program it to do over Bluetooth.