Go Back   986 Forum - for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Boxster General Discussions

Reply
 
LinkBack Thread Tools Display Modes
Old 05-25-2018, 11:13 AM   #1
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Immobilizer Compatability from year to year

Need those familiar with immobilizer compatibility between years. I have a 1997 Boxster, and the immobilizer is shot. Had ECU Repair Doctors do the diagnostics on the immobilizer and confirmed that the key fob and the immobilizer are damaged beyond repair. Since this is a "low budget" project Boxster, I am trying to stay somewhat economical in getting it running. Kind of a game..... The cost for a new key, immobilizer and programming of all the items is about $1,050, from ECU Doctors. Not a bad price, compared to what the dealerships charge, and for my 996, I would do it...now questions asked.

I wanted to know if anyone has knowledge of what year Boxster immobilizers/ECU units are compatible with my 1997. Here are the specifics of what came out of the car:

1. ECU - 99.0618.601.02 (Bosch 0 261 204 604)
2. Immobilizer 996.618.260.01 M535


I know that that it has to be an M535 and not a M531 Immobilizer. Learned that one the hard way.

I can find key, FOB, Immobilizer, and ECU for less than half that. (Yes...I know all the issues of replacement keys and VIN numbers and proving ownership)

__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-25-2018, 12:30 PM   #2
Patriot
 
particlewave's Avatar
 
Join Date: Mar 2012
Location: Ft. Leonard Wood
Posts: 6,139
Garage
Before doing that, contact forum member Qmulus. He knows his stuff and can probably fix what ECU doctors said was not fixable.
Unless the EEPROM was somehow damaged, Qmulus can fix it.
particlewave is offline   Reply With Quote
Old 05-25-2018, 12:51 PM   #3
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Thank you. I have already done that. I wanted to get this information as well. Plan A and Plan B
__________________
2002 Boxster S 6 Speed
TNT79Bronco is offline   Reply With Quote
Old 05-25-2018, 07:57 PM   #4
Registered User
 
Join Date: Jul 2013
Location: Bastrop, Tx
Posts: 2,531
Any 97-99 set will work. You can even make the 531 work in a 535 (or vice-versa)car by modifying the harness connection. All you have to do is shave off that little tab that keeps it from sliding in.
__________________
Woody
itsnotanova is offline   Reply With Quote
Old 05-25-2018, 08:41 PM   #5
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Wow!!! That seems almost too good to be true. Me being the inquisitive type, aren’t the two units functionally different? It has to be something more different than the connectors, right?
TNT79Bronco is offline   Reply With Quote
Old 05-25-2018, 08:49 PM   #6
Patriot
 
particlewave's Avatar
 
Join Date: Mar 2012
Location: Ft. Leonard Wood
Posts: 6,139
Garage
I'd have to look over the wiring diagram again to be sure of any differences, but the primary difference is frequency.

Edit: a quick glance in the Bentley manual shows quite a few differences between the M531, M534, M535 and M536. Not sure what issues may arise, but I'd take Woody's word for it.

I spent a good hour looking through the workshop manuals, but didn't find anything. It's probably around 2000 pages long, though.

.

Last edited by particlewave; 05-25-2018 at 11:17 PM.
particlewave is offline   Reply With Quote
Old 05-26-2018, 04:26 AM   #7
Registered User
 
Join Date: Jul 2013
Location: Bastrop, Tx
Posts: 2,531
I've done it once or twice to get a car running. I've also sold a couple to people who had to use a mismatch set on their boxster. I think all you lose is the ability to use your key fob but the car runs fine. There's no permanent damage to anything but the wire harness connection on the car. Even that's not a big deal as it still will plug into a 535 if you happen to go back.
__________________
Woody
itsnotanova is offline   Reply With Quote
Old 05-26-2018, 04:30 AM   #8
Registered User
 
Join Date: Jul 2013
Location: Bastrop, Tx
Posts: 2,531
A little advice. If you have the original key for the car there's no need to switch out the locks. Just transfer the transponder inside the good key into your old key. Way easier than changing the door and ignition locks. In fact, I recommend taping the transponder to the back of the ignition cover. Then you can get duplicate keys made for cheap
__________________
Woody

Last edited by itsnotanova; 05-26-2018 at 04:32 AM.
itsnotanova is offline   Reply With Quote
Old 05-26-2018, 05:20 AM   #9
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Thank you all for the advice. Very much appreciated.

That is very encouraging. This is my $700 Project Porsche (clean title) and I am trying to revive it as cheaply as possible, just as a fun exercise. Total budget is $2,500, including purchase price. It was an attempted theft, stole the radio, jacked the immobilizer and ruined the back window. Interior is shot (worn leather seat and faded carpet) and a few other things.

I found a complete ECU setup for $400, with 3 keys from a ‘97 Boxster. Seemed like a good deal.

I will shave off the tabs on the wiring harness and give it a shot in a little while, and report back.
TNT79Bronco is offline   Reply With Quote
Old 05-26-2018, 07:51 AM   #10
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Ok. Did the shaving of the tab. Got it all reassembled. Quick question.....

Does the ignition switch have to be replaced because of the different frequency? I know there is a little black box attached to it, that is part of the security system.

Also, the battery was dead. Charging it now. The windows went down, but would not go back up? Hmmmmmmmm. Any ideas. Haven’t really dug into it.

Also, the car seemed like it wanted to turn the starter. Made the typical clicking sounds associated with a dead battery.

More later....
TNT79Bronco is offline   Reply With Quote
Old 05-26-2018, 10:04 AM   #11
Patriot
 
particlewave's Avatar
 
Join Date: Mar 2012
Location: Ft. Leonard Wood
Posts: 6,139
Garage
Quote:
Originally Posted by TNT79Bronco View Post
Ok. Did the shaving of the tab. Got it all reassembled. Quick question.....

Does the ignition switch have to be replaced because of the different frequency? I know there is a little black box attached to it, that is part of the security system.

Also, the battery was dead. Charging it now. The windows went down, but would not go back up? Hmmmmmmmm. Any ideas. Haven’t really dug into it.

Also, the car seemed like it wanted to turn the starter. Made the typical clicking sounds associated with a dead battery.

More later....
Are you sure the immobilizer is good (because of the windows)?
The frequency applies to the transmitter only (for locking/ unlocking, opening trunk).
particlewave is offline   Reply With Quote
Old 05-26-2018, 10:50 AM   #12
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Success!! I grabbed the jumper cables and twisted the key. After what seemed like an eternity, it finally fired up!! Ran rough for a couple of seconds, and then smoothed out. No CEL or anything? Sweet!

Yes, I made sure all items came from a running ‘97 Boxster, before purchasing.

The windows would not go up, until I cycled the center latch for the top. Once I did that, then hit the window switches, the windows went up and then down the 1/4”, since the door was open.

Next question. Is the mileage displayed the actual mileage on the car, or from the replacement ECU?
TNT79Bronco is offline   Reply With Quote
Old 05-26-2018, 11:07 AM   #13
inveniam viam aut faciam
 
Join Date: Mar 2014
Location: Arvada, CO
Posts: 433
Just a clarification when it comes to "compatibility". What Woody is talking about is if you just want to get a car running, not have remote functionality, etc. The connectors are the same and the pinout are close enough that it will start and windows and locks should work.

If you want the cheapest way to get a car with a key or two working properly, buy a good used immo/alarm module of the same part number and get the data transferred from your damaged module to the replacement. Then everything will work as original and your car will still be the same VIN as far as electronics are concerned if you need to program the DME, add keys, etc.

So, just know that if you swap the DME, immo/alarm and keys, as far as Porsche's database is concerned, you have changed the car's identity from your car to that of the VIN of the car you got the modules from. Some people don't care, some do. I know firsthand that if someone buys a car that this was done on, and tries to add a key or remote they will get quite angry when they find out what it will take to get things straightened out again. The guy wanted it "right" so he had to buy a new lock set, immo/alarm and new remotes and pay to have it all installed and programmed. Note that was a 911 C4 Cab, but the parts, prices and procedures are all the same.
__________________
'03 S, manual, 18" Carrera wheels, PSM, PSE, Litronic, 996 Cluster, +
Qmulus is offline   Reply With Quote
Old 05-26-2018, 11:09 AM   #14
inveniam viam aut faciam
 
Join Date: Mar 2014
Location: Arvada, CO
Posts: 433
Quote:
Originally Posted by TNT79Bronco View Post
Next question. Is the mileage displayed the actual mileage on the car, or from the replacement ECU?
Congratulations!

The mileage shown is what is in the cluster.
__________________
'03 S, manual, 18" Carrera wheels, PSM, PSE, Litronic, 996 Cluster, +
Qmulus is offline   Reply With Quote
Old 05-26-2018, 12:37 PM   #15
Registered User
 
Join Date: Jun 2014
Location: LB, Germany
Posts: 1,370
US keyfobs send at 315 Mhz. ROW keyfobs send at 433 Mhz.
So the receivers / alarm modules also work at different frequencies and are not compatible.
The transponders are not different. Transponders can be duplicated.
The programming of the key fobs via PST needs 2 codes. One code comes with the key fob as a code card. The other code part is generated via PST by the car vin.

Last edited by Smallblock454; 01-24-2020 at 04:53 AM.
Smallblock454 is offline   Reply With Quote
Old 05-26-2018, 03:09 PM   #16
More of a truck guy
 
Join Date: Dec 2015
Location: San Ramon, CA
Posts: 77
Quote:
Originally Posted by Qmulus View Post
Just a clarification when it comes to "compatibility". What Woody is talking about is if you just want to get a car running, not have remote functionality, etc. The connectors are the same and the pinout are close enough that it will start and windows and locks should work.

If you want the cheapest way to get a car with a key or two working properly, buy a good used immo/alarm module of the same part number and get the data transferred from your damaged module to the replacement. Then everything will work as original and your car will still be the same VIN as far as electronics are concerned if you need to program the DME, add keys, etc.

So, just know that if you swap the DME, immo/alarm and keys, as far as Porsche's database is concerned, you have changed the car's identity from your car to that of the VIN of the car you got the modules from. Some people don't care, some do. I know firsthand that if someone buys a car that this was done on, and tries to add a key or remote they will get quite angry when they find out what it will take to get things straightened out again. The guy wanted it "right" so he had to buy a new lock set, immo/alarm and new remotes and pay to have it all installed and programmed. Note that was a 911 C4 Cab, but the parts, prices and procedures are all the same.
Yep. 100000% understand. If I (or anyone else wants) to do it right, all it takes is $1,050 to ECU doctors. They can make it “right”. Much, much, MUCh cheaper than the dealerships.

I wasn’t sure if the car even ran. If it didn’t, I could sell the setup on EBay or classifieds, for what I paid. If I paid ECU Doctors the $$, I had a good setup, for a broken car.

This way, I am running, with 3 keys and could care less about the remotes opening a convertible. Lol.
TNT79Bronco is offline   Reply With Quote
Old 03-29-2019, 07:09 PM   #17
Registered User
 
Join Date: Oct 2016
Location: Tennessee
Posts: 48
Garage
Piggy backing.

Quote:
Originally Posted by Qmulus View Post
Just a clarification when it comes to "compatibility". What Woody is talking about is if you just want to get a car running, not have remote functionality, etc. The connectors are the same and the pinout are close enough that it will start and windows and locks should work.

If you want the cheapest way to get a car with a key or two working properly, buy a good used immo/alarm module of the same part number and get the data transferred from your damaged module to the replacement. Then everything will work as original and your car will still be the same VIN as far as electronics are concerned if you need to program the DME, add keys, etc.

So, just know that if you swap the DME, immo/alarm and keys, as far as Porsche's database is concerned, you have changed the car's identity from your car to that of the VIN of the car you got the modules from. Some people don't care, some do. I know firsthand that if someone buys a car that this was done on, and tries to add a key or remote they will get quite angry when they find out what it will take to get things straightened out again. The guy wanted it "right" so he had to buy a new lock set, immo/alarm and new remotes and pay to have it all installed and programmed. Note that was a 911 C4 Cab, but the parts, prices and procedures are all the same.
I am trying to figure out what to do with my car right now. For the second time, I have an immobilizer that went swimming. (Last year, Porsche Chattanooga fixed it, but I don't think they did a good job dealing with the source of the water, so here I am again!-- When you water test the drains, the water comes out on the ground underneath, but some of it is also coming out in the floor. I think the Porsche guys just cleaned the drain, then saw that the water came out under the car and called it a day.)

Anyway, I'm at the point where it's either send my set off the ECU Doctors for a grand+, or to the dealer -- a different one this time.

Can anybody tell me why ecu doctors charge $200 more for the immobilizer 996.618.262.03 than they do for the 996.618.262.01 immobilizer? As I understand it, the .03 part number is a replacement for the .01 part number. (My original immob had the .01 number, but I'll have to check what I currently have, since I guess it's possible Porsche Chattanooga put in a .03 immob last year.)


Also, advice. Harper Porsche in Knoxville says $723 for a new immobilizer, plus $150 for programming, but they also say I'll have to buy at least one new key (with labor, about $1200 total). Why would I have to buy any new keys? I thought the new immob would be flashed for my car and my current keys would still work. Should I go with ecu doctors, Porsche Knoxville, or a third option? Obviously, I want to spend as little as possible, but I want everything to be like it's supposed to be.
Tweetdriver63 is offline   Reply With Quote
Old 04-01-2019, 09:49 AM   #18
Registered User
 
ECU Doctors's Avatar
 
Join Date: Sep 2012
Location: Florida
Posts: 24
Tweetdriver63, the difference in price is because some immobilizers are more expensive than others. But as you can see we are more competitive in price than the dealership.
With us you won't need new keys, unless you want to buy another one which we can program.
Also, with us you get 5-years warranty.
Any other questions?

ECU Doctors is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 09:31 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2018 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page