CBR786

Hello everyone I could do with some help trying to fix why my passenger central locking motor does not want to work.

brief history the car has been stripped out and had a full roll cage welded in previously and RS door cards along with Race bucket seats etc. The first question I need to ask is did all Porsche 993 models come with door handle micro switches ? the little C clamp with a white wiring loom coming off connecting to door loom?

I stripped down door cards to take a peek inside to see why my drivers central locking works fine when alarm fob pressed but the passenger door does not. I assumed a dead or poorly connected passenger C/L motor initially but this has been ruled out as I tried a replacement motor still no working I bench tested old motor which has 5 wires going into it and that worked fine when I pulsed 12V to its pins.

I noticed drivers motor works fine with alarm remote yet the drivers and passengers doors do not have micro switches. Even noticed when I felt around inside both doors I could not find a male or female connecting plug for which the micro switch plugs into ? hence I am led to think the car originally never came with them ? the loom in the doors does not look butchered or repaired unlike the alarm module loom which I will expand on in my next post.

so to sum up did all 993 cars have a micro switch inside the door panels ? My alarm fob is a two button H&P fob and I have the silver module with yellow and black plugs alarm control unit under the passenger seat in my car. (which the loom looks like it has been messed with)

CBR786

I am going to digest further firstly the passenger central locking never worked since the car has been in my ownership. The red led lights that blink on the door trims have been removed and never been present since I have owner the car. Also for some unknown reason the central locking button on the centre console in front of the gear shift lever has been removed when I undo the trim and false button in its place I see a loom plug which is loose and I believe if I buy a replacement central locking button it will fit into that bunch plug.

The quest to try to get passenger central locking led me to look at the alarm control module and I found disturbing modifications on the Black plug the following pins had the loom cut to isolate certain functions, pins 4 Black/Red (Anti-drive off feature) and Pin 8 Black/White (Turn Signal left) also Pin 9 Black/Green (Turn Signal right) Pin 10 Red/Purple (Horn).

The yellow plug has some modifications as well which I need to examine tomorrow to see exactly which pins have been cut. I did notice Orange and Blue wire had been cut and the black wire had been cut. The Black wire was loose as it came out of its connecting socket this I pushed back in for now.

The Alarm works as in if I open door when Alarm is armed the indicators starts flashing but no Horn sounds ( I know why now because the particular wire has been cut) If I try to start car with out pressing the remote the ignition will not Crank. The drivers central locking motor works as it should with the press of the alarm fob. The passenger door needs to be locked and opened manually with a key.
what I find strange is the indicators flash when alarm is meant to be sounding but the wires look like they been cut at the module? also when I press the fob the indicators flash 3 times and the drivers door locks. when I press the other button on the fob I get a single flash on the side signals/indicators and the door unlocks.

pp000830

Stripping out a car is easy, restoring it not-so-much.
You mention a two button remote fob. Is it some sort of aftermarket component? Do you see a Porsche part number on its controller?
You need a wiring diagram to put back any missing devices and wires removed in the past.
PM me with your regular email address and I should be able to send you the page involved.
Andy

CBR786

Thank You Andy for your input and help much appreciated. The two button fob is hamilton & Palmer the original Porsche alarm fob. I was surprised to see no micro switches in both door handles also no place for the micro switches to plug into either making me think that not all Porsche 993 models came with micro switches in the door ? I am thinking this because on further investigation the door wiring loom in the door cavity looks original I see the connections for the electrical window switches and the connections for electric door mirrors and window motors. I will send you a PM hopefully I can study wiring diagrams to see what goes where. If I peel back the electrical insulation tape I can see the remainder of the relevant colour coded wires in the wiring loom where it has been snipped and taped up. I guess to revert this I simply re solder the corresponding colour coded loom with each other. (I however prefer the alarm horn not sounding as this will be annoying) .

The previous keeper had it set up so when you press the Porsche fob the drivers door unlocks remotely and thats it, if you wish to unlock the passenger door you lean in to the car manually pull the latch or insert key into the passenger door lock and open it manually. The strangest thing is when car is locked via alarm fob the drivers door obviously locks but the passenger door does not but when I go open the passenger door the drivers door central locking motor sounds and unlocks the drivers door lol.

I could live with the current set up as the car is not for sale and was made to look like a GT2 track day car etc, I just thought I would have a play and see if I can get to the bottom of why the passenger central locking motor is not activating. I ideally would like the set up so when I press the fob both doors lock and unlock accordingly. I do not mind if the doors do not open together when I manually use the key so long as they both open when I press the fob. I was thinking maybe because the central locking button in the console has been removed maybe that is causing a break in the circuit which is stopping power getting to the passenger door.

CBR786

Thank you Andy,

I have received diagram via email. I now need time to try to make some sense of the pin outs and wiring colours.

CBR786

pp000830

What model year is your car? It seems that a lot of changes took place before MY1995 when the 993 was introduced into the US market.

CBR786

my car is a 1997 so was fairly late. I am in the UK hence after doing some research I found out all 993 cars for the UK market where fitted with this H&P alarm system as the insurance companies at the time refused to insure them due to the O.E alarm not passing our strict anti theft policies. The company Hamilton & Palmer where visiting main OPC centres and fitting these to zero mileage cars before being sold.

I stripped the loom back to see what is going on and my findings areas follows:

on connector 1 (The large black bunch plug that plugs into the silver alarm module 928.618.260.03) the wires that have been cut are:

Terminal 4 Anti-drive off feature RED/BLACK wire cut from going into the black bunch plug and looped into a mystery black wire going to H&P unit.
Terminal 6 Term 15 the original wire is going to the plug but another black wire piggy backs from it and this wire also goes to H&P unit.
Terminal 8 Turn signal left BLACK/WHITE cut from going to black bunch plug and looped to H&P
Terminal 9 Turn signal right GREEN/BLACK cut looped to H&P
10 Horn RED/PURPLE cut completely not going any where can see both ends of wire (can re join and horn will sound when alarm is going off)

on connector 2 (The large yellow plug that plugs into the same alarm module)

Terminal

1 Activate/closed ORANGE wire cut and looped into BLACK wire to H&P
2 Deactivate/open YELLOW wire cut and looped into BLACK wire to H&P
3 Rear Lid contact YELLOW/BROWN piggy backs with BLACK wire to H&P and original alarm module.
4 Tailgate contact BROWN/RED piggy backs and shares connection with BLACK wire to H&P
14 Diagnosis L ORANGE/BLUE wire cut and taped off looks like a factory cut and termination ?
21 Door contacts BROWN/WHITE piggy back onto BLACK wire and continue into original unit.

so when I mention this BLACK WIRE in total 9 BLACK wires all running into this H&P unit are spliced into the O.E alarm module one way or another. The Black H&P unit has another 10 or so black wires leading somewhere else which I have not bothered tracing as of yet. I only want to get the both doors opening with the remote so not bothered about removing this H&P unit after all it works in as the car starts and the drivers door locks with the remote.

What I did notice is the door handles on both sides do not contain the micro switches I feel H&P must have done this and the central locking motors are controlled partly by their unit. I also by studying the wring diagrams note that the central locking motors on both sides have five wires going into them and they are the same colours BLUE/YELLOW & GREEN/RED & BROWN & BLUE/WHITE & GREEN/WHITE.
on further analysis I think the wires lay out is : BROWN wire is earth/ground.
BLUE/YELLOW is a pulse wire to move actuator
GREEN/RED is a pulse wire to move actuator another direction
BLUE WHITE is terminal 10 central locking system position switch
GREEN/WHITE is terminal 12 central locking system position switch

my problem is this if the micro door handle switches are missing on both doors (BLUE/WHITE & GREEN WHITE) why does the drivers door actuator work ? and not the passenger side ? I am going to use a multi meter and test light probe and see if I get any pulses or feeds on the connector block for the door wiring loom which is mounted in the passenger and drivers foot wells these hopefully have a connection then my issue is a broken wire going into the door loom on passenger door. fingers crossed.

CBR786

I have had some free time to look at this again and have found pins 8,10 on the door wiring loom junction plug that sits in the A post foot well has no power going to these pins when the alarm fob is pressed, hence the reason why the passenger central locking motor is not working. These pins feed the central locking motor , pin 8 is the Green/Red wire to C/L motor and pin 10 is Blue/ Yellow. They are meant to alternate in polarity to raise or lower the motor.
What I cannot understand from the wiring diagram is a box numbered 20 and 21 what are they ? and where are they located ? also the central locking wiring according to the diagram also goes to DRIVE REAR PACKAGE TRAY what is this and where is it located ?

I will try to attach the wiring diagram with amendments so you can see what I am trying to find. The drivers door pins 8,10 same wiring colours are getting alternating power hence the drivers motor works. any help would be greatly appreciated I rather find the fault instead of running new feeds into the central locking motor.

CBR786

I did some more research and now I know what a REAR DRIVE PACKAGE TRAY is lol. I do not need to worry about this as I do not have one. I think it is a option Porsche did where you could have a rear seat delete and instead have two glove boxes and some other storage area kind of shelf fitted. I believe according to the wiring diagram they where lockable with the central locking. I do not have this so now I need to figure out what the boxes on the wiring diagram 20 and 21 are and where i can find them. I think if they are some sort of junction box then this is where my connections might be broken?

CBR786

CBR786

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Pdyson4

Has anyone opened up the CL module? My interior lights don't turn off and its the module 'Inside Lights' I/7 switched ground permanently closed. Guess there's a relay in there that needs replacing.

hotaru

Hi, I have the same problem on my 1996 - no switches on lock cylinder (from factory). I can unlock driver door and both door automatically unlock. But when I lock the door - only the door that I lock with key will lock . When I use the lock switch on the console - both door automatically get locked/unlock. I have changed the door lock motor on both sides but same problem.
Stan

CBR786

have you fixed this issue? where are you located in the UK? You need to look at all the pin connections going in the door jams on both doors maybe one pin has been slotted in to the wrong connector ? has this problem always been like this since you have owned car or has it just started happening one morning ?

has you car got the H&P alarm system ?