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I am helping a friend with an early 96 the 19th vin in the sequence. The car has a lot of gremlins albeit a solid car. A true 58k miles. It wears early exhaust tips and shifter.
When I go to plug in an OBDII scanner into the port on the center console I can't get a connection with any of the hand held scanners I have. The car has alarm issues I believe I need to pull the brains and send them out to ECU Dr to have repaired. One minute. it works perfectly but if it sit for any length of time it won't accept the signal from the key fob. If I unlock the car by setting off the alarm and holding the key to the left for 40 seconds the alarm silences and you can drive the car for a while but eventually the immobilizer will kick in and not turn off. Key fob batteries are new and all is functioning properly 50% of the time.
I will try to barrow a durametric or Altel I might even have access to a PIWIS. My concern is this might be like a few other very early 96's I have come across that had OBDII ports but needed an OBDI scanner or cable to convert to the OBDI round connector. If the ECU is not connecting it could be another problem but before I pull the seat out (which appears to have never been removed) and start drilling I was curious if anyone knows if these cars came with OBDI or OBDII and if the alarm is anything I can work with if I have a proper scanner?
I have never had an alarm problem like this but most of my electrical stuff I work on is not alarm based and I prefer the 964's for this reason. FYI someone pulled the radio and cut the harness. I was planning on installing aPCCM radio but I want to make sure this alarm issue is dealt with first.
Tony pretty sure all the early 993TT's are '96 even though it may say '95MY and come with OBDII ..Bert
I am learning. I understand the mechanics but my cars are either OBDI or OBD exempt. This makes my 928 seem uncomplicated. The alarm has become a nightmare. I have an easier time diagnosing my 70's electromechanical Pinball machines than this garbage. It is the most overly complicated SS analog system for no reason. Keeps both you and the the thief from driving the car.
I cannot get a connection using hand held OBDII readers 4 different types from Bosch to Altel and even the better Aultel tablet will not connect. I have never had an issue with the tablet on a 993 before. So I am looking for a durametric to barrow. Sad part is when the alarm works it works properly but when it times out it needs to be set off and then using the key turning to the left for a period will reset the alarm. The fob works perfectly rom 20 feet until I allow it to time out. The key fob gets locked out until the system is reset. I had a friend who is a Porsche tech go over it with me he specializes in these and even he is scratching his head.
I recall something about the trunk light or bulb if blown or removed ,disconnected or blown fuse the alarm circuit either doesn't connect or shuts down ...
maybe something to look into I know when I first started dealing with my '96TT we had some similar difficulties and it came down to the fuse for the door and trunk circuits ...Bert
I recall something about the trunk light or bulb if blown or removed ,disconnected or blown fuse the alarm circuit either doesn't connect or shuts down ...
maybe something to look into I know when I first started dealing with my '96TT we had some similar difficulties and it came down to the fuse for the door and trunk circuits ...Bert
Initially that was my thought. I replaced the blown bulb and everything appeared to work properly so I a mistakenly figured it was working. I played with fuse 11 and it didn't change anything unfortunately.
Originally Posted by Matthew Scott
All 993 TTs are OBDII, worldwide even if it wasn't required in the local market.
So Iwas able to get the car started and the OBDII port began to work and was able to read all the emissions diag. However the alarm is still acting up. I just found it strange that the car would not read the ECU even with the IMMO light out and my being able to start the car. Only once the car was running could the scanner connect with the car. Usually this is done with the key off than on again. In this case it only worked when the engine was operational.
So now I know it isn't an ECU issue I have to figure out why the alarm times out and the IMMO engaged with no way to override it. I know it is not the key fob at least. Yes it is OBDII.
I had a similar problem with my 993. Most of the time when it was turned off hot, for example to refuel, it would not start again or only after the tenth try.
I first suspected the fuel system but there was no fault to be found. On a hint of an independant I have then removed the alarm control unit under the seat and resoldered all accessible connections.
That was a good 8 years ago, since then the error has no longer occurred.The alarm control unit are prone to cold solder points.
I went over this with Loren and Jay and they were stumped a little and I had a friend who is a gold star tech check it out for 3 hours with me. We were all scratching our heads. The problem ended up being a very slight capacitor leak in the IMMO unit. I finally decided to hit the board with some electrical contact cleaner plugged it back in and everything worked. Apparently the leak created a small bridge of current to the resistor next to it. It worked for a week and then failed again. I think the cold weather might have something to do with it but not sure. In either case I was able to access the ECU after cleaning.
The red capacitor is the culprit as it seems to be a relatively common issue. It just didn't act up as they normally do. It would work so long as I kept locking and unlocking the doors from 25 feet. If I let it rest for 20 min then it would lock me out. Not sure why it wouldn't allow me to access the ECU when teh IMMO was working but all resolved now.
Not sure if you've resolved the alarm/immobilizer issue but there is an immobilizer override from Pelican parts for $350, its plug and play no cutting any wires and resolves all of these issues and completely reversible. I'm having it installed on my 98 993tt as we speak.
Not cheap but the thought of driving anywhere and getting stuck because of the immobillizer just not worth the drama.
Not sure if you've resolved the alarm/immobilizer issue but there is an immobilizer override from Pelican parts for $350, its plug and play no cutting any wires and resolves all of these issues and completely reversible. I'm having it installed on my 98 993tt as we speak.
Not cheap but the thought of driving anywhere and getting stuck because of the immobillizer just not worth the drama.
Jay from Immoblock sells a unit that is a simple install. I agree nothing worse than getting stranded for something stupid like the alarm. I believe the unit allows the immobilizer to function manually but you need to manually lock and unlock. the doors to activate? Let us know how it goes.
It's the same one I believe. Apparently works great on US cars, does not work on ROW as I have recently found out the hard way.
If anyone has a workaround for ROW cars I'd be interested!
It's the same one I believe. Apparently works great on US cars, does not work on ROW as I have recently found out the hard way.
If anyone has a workaround for ROW cars I'd be interested!
MTUK-
IMMO BLOCK does work on RoW cars - it's installed in 993s in over 12 countries. The only difference is you wire it to the car instead of plugging it in (RoW cars don't have a gong relay). You can download the RoW install manual off the website. If you have any questions, let me know.
02-15-2023, 09:10 AM
Early 95 turbo OBDI or OBDII?
