The Toecutter Posted November 23, 2023 Report Share Posted November 23, 2023 16 hours ago, phazed said: Just removed two units from under the pax seat. The smaller one with a multi pin connector I guess is the immobilizer. The other one has two large multi pin connectors, and to me. This looks very similar to the one that is under the seat of my 987.1. Haven’t looked at the wiring diagrams yet, but hopefully this will shed some light on the subject. I would have thought that someone here may know the definitive answer what this larger ECU is for. ??? The big one with the two multi plugs is the immobiliser module. The other small one is park assist maybe? And yes it does do other things, central locking, window control and things like that. It is almost like a body control module, but old school with relays and things. Quote Link to comment Share on other sites More sharing options...
CRC Posted November 23, 2023 Report Share Posted November 23, 2023 (edited) I feel your frustration regarding the roof and the whole double relay issue. Min was also stuck in the "roof up" position and eventually got it open by reaching through and removing the two spring clips on the clam shell ...... really not easy, but just about doable. Shown below are some graphics of my attempt to solve the issue by taking out the double relay ( it's way more than just two relays in there as you can see.) The wiring diagram was my attempt to fault find (98 2.5 Boxster), but in the end I gave up and became an advocate of the manual system .... which works perfectly every time, in all weather .......... https://imgur.com/Wq6s5S1 https://imgur.com/4GLW9i5 https://imgur.com/YRiHoVG Why can I never seem to get Imgur image links to actually show as graphics in the post? Edited November 23, 2023 by CRC Quote Link to comment Share on other sites More sharing options...
phazed Posted November 23, 2023 Author Report Share Posted November 23, 2023 Thanks guys. Hopefully will have time a little later to open up the unit and assess damage. About to have granddaughter delivered so house will be upside down till about 4 PM so will probably have no chance! Plan A will be to open up the unit, cleanup, terminals with a soft brass wire brush and contact cleaner, ditto the plug which has green evidence in the car and see where we go from there. Plan B will be to manually disconnect the roof so I can carry on with other work on the car. Part of me considers removing the roof completely and sourcing a hardtop as it is just for Track Days but alternatively, it is really nice to have the roof off in good weather when barreling around a track… Can’t believe the cost of the unit. I guess because it is a rarity now the price certainly hasn’t gone down. No wonder the previous owner sold the car when he had a quote from a Porsche main agent to rectify not just that fault but all the other faults that I knew about and others that I have since discovered! Quote Link to comment Share on other sites More sharing options...
The Toecutter Posted November 23, 2023 Report Share Posted November 23, 2023 39 minutes ago, phazed said: Can’t believe the cost of the unit. I guess because it is a rarity now the price certainly hasn’t gone down. No wonder the previous owner sold the car when he had a quote from a Porsche main agent to rectify not just that fault but all the other faults that I knew about and others that I have since discovered! Yep, looking through older posts people are mentioning £3-400 but those days have long gone. Even used the sellers are asking quite a bit of money for them though. If you go the used route (as I did) you have to either replace the immobiliser module and engine ecu as a matched set (with the corresponding keyfob and transponder), or if just replacing the immo module you'd need to have your old one cloned into the replacement one (the eeprom just needs swapping if you are handy with soldering). You also have to be a bit careful to match the part numbers with your old units. You'll probably have more choice with a later car, but mine being an early car there were very few suitable used ones about in fact only one came up recently, which I bought, and none since. Quote Link to comment Share on other sites More sharing options...
phazed Posted November 23, 2023 Author Report Share Posted November 23, 2023 Again, thanks for the information. Gives me more to go on. Quote Link to comment Share on other sites More sharing options...
½cwt Posted November 23, 2023 Report Share Posted November 23, 2023 26 minutes ago, The Toecutter said: Yep, looking through older posts people are mentioning £3-400 but those days have long gone. Even used the sellers are asking quite a bit of money for them though. If you go the used route (as I did) you have to either replace the immobiliser module and engine ecu as a matched set (with the corresponding keyfob and transponder), or if just replacing the immo module you'd need to have your old one cloned into the replacement one (the eeprom just needs swapping if you are handy with soldering). You also have to be a bit careful to match the part numbers with your old units. You'll probably have more choice with a later car, but mine being an early car there were very few suitable used ones about in fact only one came up recently, which I bought, and none since. Official part will always go up by their annual increases regardless of the age of the part. And manufacturing old tech is often very expensive or not even possible. Perhaps we have reached peak 986 scrappage? Quote Link to comment Share on other sites More sharing options...
TV8 Posted November 23, 2023 Report Share Posted November 23, 2023 1 hour ago, phazed said: Part of me considers removing the roof completely and sourcing a hardtop as it is just for Track Days but alternatively, it is really nice to have the roof off in good weather when barreling around a track… I was going to suggest that. The hard top is not that heavy and could be left on the trailer if you want the lid off. It would save a few KGs getting rid of the soft top... Quote Link to comment Share on other sites More sharing options...
Paul P Posted November 23, 2023 Report Share Posted November 23, 2023 Big confused here. What are you chasing right now. ? Roof and windows or something. Related to starting the car or the alarm. 986 under seat module is alarm / immobiliser. Doesn’t run the roof. And roof can be opened via the physical removal of connectors if you want if need to fix the roof, I think look elsewhere You only need to worry about the alarm / immobiliser unit if there are issues with starting the car. Jmg Porsche ( search for 996 alarm primer ) have a write up of how the whole system hangs together and offer some services on “fixing/coding stuff” if that’s the issue (I seem to remember the “breakers” fix is keys/ignition/alarm/dme as a set. ) Apologies if I have misunderstood. Quote Link to comment Share on other sites More sharing options...
phazed Posted November 23, 2023 Author Report Share Posted November 23, 2023 It seems I have several problems. Apparently, the car did not start some months ago because of water that got into the immobiliser unit. That was dried out and the car runs. I have cleaned up the connectors and the pins to this unit today. They did have some green corrosion. Haven’t put it back in my car yet. The roof not working, which I thought was connected to the under seat unit must be a different problem and I will be looking at that tomorrow as well. If I can’t see anything obvious, then I will manually lower the roof as discussed. The electric windows do not work, and I wonder if there is a module controlling these or if that could be an easy fix. Something else I need to investigate. Quote Link to comment Share on other sites More sharing options...
phazed Posted November 25, 2023 Author Report Share Posted November 25, 2023 Did the bang and shake of the double relay, no change. Immobiliser terminals all cleaned and plugged in. I know the car runs so that is a positive. Next step, disconnect roof and lower manually, roof operation on back burner for now... Quote Link to comment Share on other sites More sharing options...
Fat Rat Posted November 25, 2023 Report Share Posted November 25, 2023 3 hours ago, phazed said: Did the bang and shake of the double relay, no change. Immobiliser terminals all cleaned and plugged in. I know the car runs so that is a positive. Next step, disconnect roof and lower manually, roof operation on back burner for now... I suggest trying your relay in another car to prove. At least that will prove something. There are 2x relays, an early and later version. 🤙 Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 I have left these problems for awhile, as I had plenty of other things to get on with. I knew the ignition switch was past being dodgy, so I thought I would wait until a new one was fitted. Fitted new ignition switch and ignition lights all go off as they should. Nothing else really solved. At the moment headlights are removed and all brakes disconnected. I have bridged the connector for the handbrake while awaiting a new switch. I have the single microswitch in the interior light cluster that immobilises the roof operation and that seems sound. With the ignition on, I have the following: All ignition lights illuminated. Handbrake warning, light constantly on. Cruise control, light illuminated, even though switched off. Heater controls all work. PSM light on switch, illuminated no matter what. Door locking switch, not working Heated window switch, not working Window switches not working Wipers and washers working Horn working Indicators working Spoiler is up Windows do not drop when unclipping the roof handle. You can run through the on board dash display, all seems to work. Both keys, even though new batteries fitted, don’t seem to do anything apart from turn the ignition. That is just a flavour of what seems to be connected problems. The car did have water ingress and the immobiliser dried, terminals, cleaned and car will turnover and start. it seems to me, without comparing it to another car that when you switch, the ignition on all lights should illuminate, and then some go off like the cruise, control light, handbrake light when it is lowered and probably a few others until the engine actually starts. Can’t start the engine at the moment as all oils are drained but that should have nothing to do with the problems above. If it were my 987.1 I would say just renew the unit under the passenger seat, but allegedly this is completely different. HELP! Quote Link to comment Share on other sites More sharing options...
nelmo Posted December 4, 2023 Report Share Posted December 4, 2023 (edited) I've lost track but is this not your car? Are you just trying to help someone out? Why on earth did they buy it in this condition? 🙂 Ah ok, just re-read the thread and it is yours...sorry for all these issues, I would be tearing my hair out and 'doing a Fawlty' on the car by now... did you not notice any of these issues when buying? Or was it really cheap and the hope was to fix them all? Edited December 4, 2023 by nelmo Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 Was cheap and I knew the immobiliser had been wet. Picked it up from a Porsche dealership, (straight on a trailer) that had given it a health check and had picked up the usual, brakes, pipes etc. Obviously nothing else listed above! Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 I do have a friend and neighbour who has an early 2.5. Would his car have the double roof relay that I could swap and try? Quote Link to comment Share on other sites More sharing options...
½cwt Posted December 4, 2023 Report Share Posted December 4, 2023 9 minutes ago, phazed said: I do have a friend and neighbour who has an early 2.5. Would his car have the double roof relay that I could swap and try? The convertible top relay changed for the '00 model year. 986 618 111 02 up to '99 and 986 618 199 00 from 2000 onwards. Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 So that won’t work as mine is a 02. Quote Link to comment Share on other sites More sharing options...
TV8 Posted December 4, 2023 Report Share Posted December 4, 2023 You can have a try of my 2001 relay next time I am local if you don't mind waiting or pop over and borrow it if urgent? Assuming the part is accessible? Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 Thanks Graham. The part is very accessible. Any ideas when you might be in the area? failing that I’ll have to organize a run out. Quote Link to comment Share on other sites More sharing options...
Nobbie Posted December 4, 2023 Report Share Posted December 4, 2023 There may not be any issue with the roof mechanism as you say the windows are inoperable. I assume there are microswitches to confirm window drop before roof operation commences? I’d try and fault find the window operation before doing any dismantling of the roof mechanism. Do the windows drop when opening the doors? Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 Was thinking along the same lines. When I fiddled a couple of weeks ago, the windows dropped occasionally, nothing else. They do nothing at the moment. Thoughts are that there is something affecting windows, roof and spoiler, (spoiler may be a separate issue I guess). I printed off the list of tests that you can do with the relay removed. Bridge certain terminals and check results with the sheet. Got other things to do first so will get back to that soon I think as it is starting to p*ss me off! Open to suggestions though... Quote Link to comment Share on other sites More sharing options...
Daboy3000 Posted December 4, 2023 Report Share Posted December 4, 2023 I can't remember if it's been asked but how is the box under the passenger seat? if it's been wet it could be causing some of your issues. Quote Link to comment Share on other sites More sharing options...
Nobbie Posted December 4, 2023 Report Share Posted December 4, 2023 This might give some pointers, it’s on a 2003 911 Turbo, but window circuit should be similar. Fuse C3 seems to be an issue on that one. https://rennlist.com/forums/996-turbo-forum/1032221-short-in-window-and-door-circuit-help.html Quote Link to comment Share on other sites More sharing options...
½cwt Posted December 4, 2023 Report Share Posted December 4, 2023 (edited) I think using the wiring diagram to find the cable routings and any water damage where there are junctions. Could be something really weird like corrosion on the pins in the A Pillar socket so the control system doesn't know what the door lock module and windows are doing. This is a spit ball idea not a serious suggestion to track down, but it may well take time and patience. Edited December 4, 2023 by ½cwt Quote Link to comment Share on other sites More sharing options...
phazed Posted December 4, 2023 Author Report Share Posted December 4, 2023 Thanks guys. Something I will approach when I am in the mood. Putting the suspension back together now so need to manually unclip the roof, which is annoying! Need to get to the three nuts on each side to release the suspension units. Quote Link to comment Share on other sites More sharing options...
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