Champagne

Hey all,

I am in the process of installing a remote door lock.
For the constant 12+, would the best solution be to bring a new wire from the battery?

If so, what is the best way to do this?

Also, in the same project, I need to feed the horn circuit to get a chirp lock confirmation. From the schematics, it would appear that grounding the br/wt wire connected to pole 85 of the horn relay would accomplish this. But I'm far from sure, could someone confirm this please.

Thanks

Paul

Alan

Paul,
Not really required, it isn't great to have too much 12v battery direct wiring snaking around the car - but fuse it right after you tap into it and make sure you have a good connection - bolt/solder/real connector.

What eaxtly you do depends where you want to install the entry system - you could go with central electric somewhere and even use an unused fuse slot?

I have my keyless entry where the amp used to go - under passenger internal rocker cover thing... works fine - you may have less room if the amp is still there.... - anyway I tapped into (soldered & shrink wrapped joint) the hot wire left over for the amp - I'd have done this if the amp was still there also..

For my model year the alarm is under he passenger seat so its easy routing for the open/disarm & close/arm wiring - also makes it easy to flash the indicators, sound the horn and helps with releasing the hatch - though that needs more wiring - seems this location is OK for the antenna which I was worried about - no problems @20+ feet all around the car.

For the horn I used the connection on the alarm (for the alarm horn - different one I think) The alarm has an internal relay so I needed a seperate relay (also needed one for the indicator flash). In the end I have disabled the horn honk - too much every time! I find the lights are enough....

Alan

Champagne

Hey Alan,

thanks for the input. I'm following one of your earlier posts for the install

That answers my question for the 12+.

My lock/unlock alarm control box is under the radio. That's where I will tap for lock/unlock functions.

As for the horn, I also found a re/wt wire in the same control box that seems to feed the alarm's horn. But I don't know if I should sent it ground or 12+ from the relay. I assume ground.

The relay I'm setting up for this horn will have:
- a wire coming from the new module going to pole 85.
- Terminal 86 will have 12+.
- Terminal 30 will go to that re/wt horn wire.

I need to know if I should put ground or 12+ to terminal 87

Thanks again

Paul

Alan

Paul,
12+ - The clue is in the wiring colors: red = +12V Battery, Red with a stripe = switched 12v, Brown = Ground, Brown w/ stripe = switched ground (Porsche uses switched grounds a lot as obviously you are familiar with).

I did also check the wiring diagrams for your '88 and indeed the other side of the horn goes straight to Gnd (brown wire). Seems you have a somewhat different alarm setup.

Alan.

Champagne

Thanks again Alan,

that makes a lot more sense now.
After reviewing the alarm schematic on page 9 for my88, it does seem that indeed the alarm horn is switched by the 12+.

You have no idea how this simple explanation as made reading these things much easier

I will be using your description of the relay connection for the trunk release.
I will post a schematic of how I understand it later to make sure.

Thanks again

Paul

Alan

Paul,
Remind me of that previous thread. I recall Roger Tyson & I were discussing this and I ended up totally rewiring my install - mainly because when I went out to check it for Roger I though it looked like a hopeless heap of wires - and I'm always bitching about the mess the previous owner made so...

So its now neat and tidy and I changed the way the hatch was wired which would make it easier to do from scratch.

I think much of the final detail was shared with Roger in PM's - so you may have some out of date info...

Briefly:

You have to rewire the hatch motor ground because stock it will only run with the doors open (no good). You must also disarm the alarm as you unlock the hatch for obvious reasons - you will need a relay for the hatch and will need to route the hatch release button* O/P wire to the keyless entry/relay location and a new wire from there to the hatch motor.

I can scan in the latest schematic I made for this if you like - I reused some existing wiring to minimise new stuff to do.

* only if you need to maintain the hatch release pull function

PS If not stick it in an envolope and send it to me - I'll pay you for it

Alan

Champagne

Hey Alan,

this is the thread:https://rennlist.com/forums/showthre...7&page=2&pp=15

It sounds like the same thing you are describing but I would certainly appreciate the schematic if you have it. I'm sure others would like to see that too.

Thanks

Paul

Alan

Paul - yes that describes the later version well. No changes from that but it may not be fully obvious from just the text ... don't know? it was/is clear to me - but then I already did it! Here is the schematic:



In the image the highlighted wires are all new additions

This assumes you only have a drivers side hatch release, also assumes you want to keep it and maintain the safety feature that you cannot pop the hatch with the pull with the doors closed (can from from the keyless entry fob - I thought that was OK for safety). Assumes your keyless entry has negative O/P's for lock/unlock & hatch.

If you have a 2 stage unlock output you could use that for the hatch combined with (just connect together as I did) or separate from the hatch release.

I also added anothe relay for the horn as we discussed - it can be programmed for Panic and open/close beeps. My keyless entry also had a built in +ve lighting relay so I used that with 2 diodes to connect to the indicator circuits to flash the orange indicators when locking/unlocking - all pretty easy stuff...

Hatch was by far the hardest - but works great now.

Alan.

Alan

All,
Note that my schematic was for a GTS and it seems there are some differences on earlier cars. One example - the GTS hatch when opened does not unlock/disarm the doors - I think this is different on some models including on Pauls '88. There is no Brown/Blue for the hatch it just duplicated the doors unlock/disarm & lock/arm - so you'd have to use the Brown/Green instead (e.g. a general unlock/disarm). This seems to imply the doors are unlocked every time you unlock the hatch - right?

The GTS when you open the hatch just suspends the alarm until that hatch is closed then automatically arms it again - seems the 88 probably doesn't do this - so after closing the hatch you'd need to lock the doors to arm the alarm again - I assume?

Could be other differences...

BTW I also discovered a mistake in the FWM's '88 page 9 the wiring to the L/R door locks is screwed up! end colors are right, line drawing is wrong, probably should have followed same sequence as the hatch lock...

Its also odd that the owners manual really doesn't do an adequate job of describing how the alarm works - took me a good while to figure it all out. (more so because mine was connected wrongly courtesy of the PO )

Alan

Champagne

Thank you so much Alan,

I will tackle the job tomorrow. I will post comments if there are specific adjustments to be made.

Paul

Champagne

It would appear that the project will end up more complicated than I initially thought.

It seems that in model year 87-88, the door lock circuit and the alarm circuit are separate and different.
I assumed that gounding the yellow and gr/bk wires in the door lock module (found under the radio) would accomplish both tasks. But this only locks/unlocks the doors.

It also appears that grounding the proper wires on the alarm module (found behind the glove box) will only arm/disarm the alarm.

So I guess my only choice is to bring wires from my remote module to both the factory locking module and the factory alarm module.

Half the interior will be dismantled by the time I get through with this

The question now is: since the locks seem to need a longer pulse to operate, will that be a problem for the alarm since the same wire will pulse both systems.

Thanks

Paul

Alan

Paul,
Humm - I didn't look into your years locks/alarms specifically. Alarms & locks did vary a lot through the years!

Assuming both are available in same location and work OK it shoudln't be too hard. Longer pulses should be fine for the alarm - just like you hold the key turned longer sometimes...

You will need to do more than just wire these together though - you will need a diode on each line to ensure the circuits aren't shorted together - local radio shack will have some that will work fine. I'll tell you more after a brief look - may take a day or so...

You'll get there - but its never as easy as you think it will be!

Alan

Champagne

Hey Alan,

again I find myself in your debt. I had a feeling it wouldn't that simple.

The only other S4 I know of who did this is Tony and he didn't have a factory alarm. I'm sure the research you are doing will be useful to many.

Thanks again

Paul

deliriousga

In my '87, I found that the module by the passenger seat (in the box under the hatch button) also powers the alarm system. I was messing with my radio wires and unplugged that box thinking it was the factory amp. After looking closely, I saw the amp is already gone and the PO had bypassed it.

After unplugging that box, the locks still worked, but the alarm did not. I realize that's still a seperate circuit when I unplugged it, but maybe there's a way to combine them in that area. That little box also powers the stereo. Don't know if that will help, but who knows.

I'd love to know if you figure it out. I really miss remote locking, but don't want to give up the alarm. I'm also afraid if I disconnect the alarm, my car won't start one day.

Champagne

Hey John,

I guess that's another difference between 1987 and 1988.
On my car, the only 2 module under the passenger side hump is the radio amp and the module that controls the fans.
The alarm module is clipped the metal tube behind the glove box in 1988.

But it would seem that in both years, the two systems are indeed separate. So the solution that Alan is researching will work for both even if the location of the connection is different.

On the upside, yours will be easier to reach

Paul