993turbo

Hi there,

Ive been doing a lot of searching on this topic, but I have not found the info I need.

I want to install keyless entry in my 84' S with Original Central locking and alarm. The car also has the central locking button in the dash.

I want the following functionality; when I lock the car the doors should lock, and the alarm arm / Unlock and disarm the alarm

Any info / writeups on this so I do not need to reinvent the wheel.. ?

Mrmerlin

dont do it,
leave the car wire harness stock,
use the key to lock the doors.
Usually installing aftermarket systems such as alarms and door locks and remote starters will cause the battery go dead and or short out other systems in the car.
Unless your an ALAN virtually every add on system has caused more problems than its worth IMHO
Another option would to be ask Alan see what he thinks.

JHowell37

+1 on what Merlin said. Trying to integrate something else into the locking system is only asking for trouble.

Bill Ball

I'm not sure I understand the warnings against doing keyless entry. I've done this on later cars, S4s and GTS, with no issues whatsoever. Many of us have. And with assistance from Alan, Ed Scherer and others, we have come up with installations that are clean, require no serious hacking and do not cause problems. I've always just linked into the factory alarm so there is no issue with an add-on alarm that can malfunction. I don't enable the accessories in the remote locking/alarm box that disable ignition or do remote start.

Anyway, I have not looked at early cars and what would be required. Alan and/or Ed could probably advise best. There might be things that make this a bad idea in early cars, but I'm not sure what. The early locks are vacuum actuated, but if there is a central lock button on the dash, then there is a point already for electronic interface. If you avoid the add-on alarm functions, this should work without creating parasitic draw or starting issues.

The keyless entry kits have essentially standardized wiring requirements: constant 12V, switched 12V, ground, door open/door closed (which ideally are linked internally to the factory alarm deactivation/activation). Everything else is optional. The early "current flow" wiring diagrams that don't have wire color indications are utter Greek to me. I have learned the language of the later diagrams enough to stumble through them, but not the early ones. However, it appears to me that if you have the factory alarm, you can focus on the "additional wiring diagram for burglar alarm" (last page of the wiring diagrams), to locate nearly all the interface points. From a quick look, it appears that CE panel plug Z3 is constant 12V (30), Z6 is switched 12v (15), Z2 is ground (31). If you want horn acknowledgement, CE panel O2 is one access point as indicated on page 1A. Then all you need is door open/closed with alarm interface. That one I'm not sure about. Whether pins E and A at the alarm will work or you also need to interface at the central locking button or control shown in diagram page 3 or both is where I fall apart electrically. But Alan or someone else will decipher this and add comments about where things like diodes would be needed.

993turbo

Thanks for the input so far.

A: I will do it, and Im not worried about doing it. I see no issues whatsoever.

B: Only the very early cars had the vacuum operated central locking. My doorlocks are operated by a motor in each door. Albeit the motors operates somewhat slower than the ones on the newer cars and there is no comfort closing of the windows. This is all original.

What I am installing is not ''remote start or an additional alarm'', its merely a remote controlled relay giving a open and closed signal (be it positive or ground) to activate the central locking and I would wish that this also activates the factory alarm.

So, if anyone have done this job on these cars before, I would like to get some input :-)

danglerb

I had the best shop in town with experience on other 928's install mine, then the best auto electrician I know fix it, and not for one second has it worked as well as the factory system.

I used an Audiovox brand because the installing shop recommended it.

Current issues, wind sets off the motion sensor, ditto the most minor touch on the car. Runs the battery down, and as it gets low sets off alarm, and it gets out of sync with the factory alarm, as in I haven't found a way to not set both.

Search on crimestopper for some older threads with better luck.

993turbo

@ danglerb: Im not sure how your issues with an aftermarket alarm relates to me installing a relay for controlling my excisiting ORIGINAL PORSCHE FACTORY INSTALLED central locking and alarm.

Why should I search on crimestoppers??

Leon Speed

I have one because it is required by the insurance company where I lived. It works fine, but I had to fix the random alarm activation. This was caused by bad contacts, such as the door pin switches. So basically make sure all those contacts are clean.

Bill Ball

If the car has no factory alarm, then you get into more complicated installs. Still, I think with our 928 electrical resource guys here, a good DIY install plan can be made for early cars. Motion sensors are an external issue that has nothing to do with how an alarm is wired. They are troublesome and I just don't wire them in, and if you have to use them, expect some adjustment problems.

If you have the factory alarm, then adding keyless entry that does not screw up anything can be DIY, again with a little guidance form our 928 electrical resource guys. And I would DIY with their guidance rather than allow some other alarm installer who has no familiarity with 928 alarm electrics try to wire it properly.

993turbo

As written above, my 928 has both Factory Central locking and Factory alarm. I dont see any issues at all with this install.

Im merely looking for info on where best to tap into the wiring, so I dont need to reinvent the wheel. If this has not been done before, something I doubt, I will still do it. :-)

Bill Ball

Sorry if I went off on a side line. I just wanted to address the warning comments. I edited my first post to add some hook up points for keyless entry, but I'm not clear on just where is the best place to wire in the actual door lock and alarm activation/deactivation. It may be at the alarm or it may require interface at the central lock unit. Some diodes will probably be called for. It has been done before but I can't find any clear documentation here for early cars, like we have extensively for S4 and GTS. So, Alan, Ed or someone else will jump in soon enough.

Spun

It was done on my 79, but I think all of the door items were added from a later model. If you need some info from mine, I know the new owner well and can go and look. Let me know.

Alan

It should be quite easy.

Don't wire anything for dome light control.

You can indeed connect at the Z plug on the Central Electric Panel

As Bill noted correctly:

Constant power: Z3
Ignition Power: Z6
Ground: Z2

You can use the alarm horn but need to intercept the HN wire on the alarm modeul plug (needs a relay driven +ve feed).

The alarm's arm/disarm come from the hatch& L/R door locks - at the alarm module they are grounded when temporarily activated so you need a ground pulse from your Remote KE unit to drive them (this is the normal KE O/P Polarity so should be easy).

A = (Brown/Green)Disarm (via diode to "unlock" on KE)
E = (Brown/Red) Arm (via diode to "lock" on KE)

On an '84 the locking and alarm units are separate - to keep them functionally separate you should use small diodes to keep the systems isolated. So feed the above signals from your KE unit via small diodes (radio shack) 500mA - 1A are fine with PIV at least 25V. The diode end with the white ring is the cathode terminal and this should go to your KE unit output.

The locks require you also connect diodes from the same KE signals For Unlock (disarm) and Lock (arm) these use the same kind of diodes again in the same configuration (cathode to KE unit) . The signals they connect to are on the central locking module.

Pin 3 = (Yellow) *Unlock (via diode to "unlock" on KE)
Pin 5 = (Yellow/Black) *Lock (via diode to "lock" on KE)

* I believe these are the correct functional assignments - but its possible they are swapped.
Once you locate these wires simply test which causes a lock when briefly grounded... (locks must be unlocked - else will do nothing)

The pulse length of the KE is important with these motors - they may not operate correctly if the pulse length is too short.

Always try to find a dedicated minimal KE only unit - not a defeatured Alarm unit - for the minimum power in quiescent state.

Alan

blown 87

I have seen maybe a hundred of them that worked just fine when they were properly installed in the dumpster.
I literally have taken at least a hundred aftermarket alarm/keyless entry type systems off of cars to repair them.
Most had one thing in common, they all seemed to work well after the bugs were worked out for a period of time, usually about a year.

That being said, I am sure your install will be fine.

Bill Ball

Alan has you covered less than 7 hours after the original post. Amazing.