Key and locks not communicating

[magno_grail]

You should list the model number or year when posting about re-syncing the remote. From what I have been able to determine, the 986 does not use the rolling code and the On-Off-Remote button does not work. I think the 987 (2004-2012) does.
The remote and starting/unlocking/alarm are different systems. The remote just tells the CLU to lock/unlock the door or trunk (and sets the alarm by locking/unlocking the door). The RFID pill in the key lets you start and the mechanical key in the door locks/unlocks/sets the alarm.
Be grateful you have a mechanical key. A recently acquired Volvo (a real grannie scow) had remote problems. With their "emergency" key (which the dealer wants $200 for) you have to pry off the lock cover to use. You think having to open the trunk by the inside latch is an annoyance.

[ike84]

Originally Posted by magno_grail

You should list the model number or year when posting about re-syncing the remote. From what I have been able to determine, the 986 does not use the rolling code and the On-Off-Remote button does not work. I think the 987 (2004-2012) does.

The remote and starting/unlocking/alarm are different systems. The remote just tells the CLU to lock/unlock the door or trunk (and sets the alarm by locking/unlocking the door). The RFID pill in the key lets you start and the mechanical key in the door locks/unlocks/sets the alarm.

Be grateful you have a mechanical key. A recently acquired Volvo (a real grannie scow) had remote problems. With their "emergency" key (which the dealer wants $200 for) you have to pry off the lock cover to use. You think having to open the trunk by the inside latch is an annoyance.

Magno, what you said is not accurate. The 986 immobilizer system does use a very advanced (even by today's standards) rolling code system to communicate between the fobs and the immob. This is why the keys can become out of sync with the unit and programming a new key requires the iPas codes to sync the new transponder to the system. The immobilizer is responsible for control over ALL security aspects of the vehicle. There are not separate pieces of the system, it is a single piece of hardware utilizing encoded programming to interpret signals from multiple inputs and correspondingly run several different routines through multiple outputs under specific circumstances. The closest thing anyone has come to hacking or bypassing the system on the user level is installation if aftermarket remotes. ECU doctors claims to have reverse engineered the hardware and broken the software encryption but I can't speak to that further because I don't have any first hand knowledge beyond what they've published online.

All of this is detailed in the owners manual, the FSM (which is where the "on-off-remote" technique screenshot I posted came from), and wiring diagram. If you (or anyone else for that matter) needs copies of these materials, I'm happy to provide them at the low low cost of free-99

This will come off as dick-ish but please don't speculate based on what you know of the 987s. I'm really not trying to he harsh, it's just that the system is confusing enough to understand and it makes it difficult if misinformation gets posted.

On the other hand, I feel you about the Volvo situation. My uncle used to have a Volvo S80 (bad ass sedan during it's time... That was the first car I ever got over 110mph lol). We were golfing one time and he locked the keys in the car and his clubs in the trunk. Talk about a cluster****************!

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[magno_grail]

The on-off-remote button does not sync a '98 or '99 by experience. The reference to the 987 difference comes from searching the internet which, as you can tell, has a lot of bovine excrescence on it.
Not a very advanced system if a key becomes out of sync because it is not used for a while.
I have the Bentley manual for wiring and simple repairs. I went through all the immobilizer wiring when it went belly up from water ingestion.
From experience, if you change out the EEPROM from the old immobilizer to the new one you do not need to have a "dealer" program it.
Maybe sometime when I have nothing to do I will put a logic analyzer on the EEPROM and see what is being read from it. I presume when a key is inserted, the FPGA reads the list of stored RFID keys and compares them to the signal from the ignition switch. Then all I have to do is read the code from the non-working key and program it into the EEPROM list.
Same with the immobilizer/DME. They claim the immobilizer can only be programmed once but the name EEPROM says it can be programmed many times. The FPGA programming is what keeps it from being reprogrammed. The immobilizer checks the code programmed into the DME with what is in the EEPROM.
The immobilizer controls all the security but the radio remote and RFID pill are separate inputs. You do not need a remote to start the engine but you do need the RFID pill. The pill will not unlock the car but the mechanical key will.
If someone is going to steal a car they will just put it on a trailer. More typically it is smash and grab.
I find the annoyances of a remote outweigh the advantages.