Has anyone figured out how to bypass an OBDII passkey III starter enable pin # 76 on C-2 (clear connector)engine is from a 2000 Buick Regal? Is it the same as bypassing a fuel enable on eairler modles looking for 50 Hz? need anyones help and advise.
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10:34 PM
PFF
System Bot
Dec 1st, 2003
Darth Fiero Member
Posts: 5921 From: Waterloo, Indiana Registered: Oct 2002
Scott, I just got done diagnosing a 97 Park Avenue that supposidly had the Pass-Key III system. According to the info I could get from ALLDATA ONLINE, the magnetic signature of the ignition key is read by the pass-key III module. When the correct signature is read by the module, it will send a "fuel enable password" to the PCM thus allowing the car to start. The information I got went on to tell me the that the pass-key III system has 3 security modes:
1) No crank, no start 2) Crank, start and immediately shut off 3) No crank or start for 30 seconds and then allows start and run.
Information on these "new" systems is hard to come by if you don't work at a dealership. ALLDATA talked about a seperate module for the PASS-KEY III system but did not give a location. It also stated that the PASS-KEY III system can be put into "learn mode" in order to learn a new key signature but again it did not explain how this could be done.
I know you can buy aftermarket modules that are supposed to "bypass" the key signature circuit for remote start systems but this will not help you if you don't have a PASS-KEY III module. I do not know if the PASS-KEY II module will work with a PCM that is supposed to have a PASS-KEY III system. Knowing GM, my instincts tell me a II system will not work. If you could get ahold of a 2000 GM serivce manual it might go into detail of how the system works and what kind of signal it sends to the PCM. Other than that you need a digital scope and someone's car that has a P-K III system so you can see what the signal is and try to duplicate it. Sorry I could not be of more help.
------------------ power corrupts. absolute power corrupts absolutely. Custom GM Chip Burning | Fiero Engine Conversions | Turbocharging | dtcc.cz28.com
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01:51 AM
StansGT Member
Posts: 914 From: Schoolcraft MI, USA Registered: Jul 2001
Try deleting the keys on the ECM,, then see what it learns, try to start it after that.... It'll probably start, if you have all the rest hooked up right!
If it's too much hassle, would it not just be easier to run a passkey II and compatible ecm? It's still a s2 L67.
I agree. If you want to keep the OBDII computer you can switch to a 98 GTP PCM which was still pass-key II. I don't think your engine or tranny would know the difference. The GTP PCM's have better aftermarket reprogramming support than what you have now anyway.
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02:11 PM
StansGT Member
Posts: 914 From: Schoolcraft MI, USA Registered: Jul 2001
According to the info on a 2000 Regal, it is PassKey II. But the key is read by the BCM then it sends a message if its ok to start or not, over the class2 serial data line #58 C-1 to the PCM. So the BCM actually determines if it is the “correct” key, I don’t know of any easy way of faking the BCM message to the PCM. Maybe this will help explain it better then me, hope it helps.
Important If the wrong ignition key is used in an attempt to start the vehicle, a Data Trouble Code (DTC) will be set and the Body Control Module (BCM) will not send a fuel enable or starter enable message to the Powertrain Control Module (PCM) for three minutes even if the correct ignition is used.
The Pass-Key II® Theft Deterrent system prevents vehicle theft by disabling the starter motor and fuel system. If the Body Control Module (BCM) dose not identify the use of the correct ignition key to start the vehicle, the (BCM) will communicate a message to the Powertrain Control Module (PCM) which will disable the crank relay and fuel delivery to the engine.
When the (BCM) identifies the use of the correct ignition key (resistor pellet) to start the vehicle, the (BCM) will send a fuel enable and starter enable message to the (PCM) which will allow the vehicle to start.
------------------ You Don't Know the Power of the Darkside
OK, if the 2000 regal is the same as the GrandPrix, You're already covered. I'll explain.
If you don't use the Body Control Module (which you won't if it's in your fiero), the passkey III is not needed. No need to bypass anything.
I state this as a fact, because my 3800SC fiero runs just fine without it. I did buy the PKIII module AND key from the original donor vehicle (2000 GTP) but never used it.
Before I knew this, I test-fired my car and it ran great. It was very confusing at first, but without the BCM, the PCM doesn't even look for PKIII.
Hope this helps.
-Tim
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11:21 PM
Riceburner98 Member
Posts: 2179 From: Natick, Ma, USA Registered: Apr 2002
Just thought I'd throw this in there - saw it on eBay and it reminded me of this thread. Don't know if it helps, as I have zero experience with Passkey III. http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=2445079094&category=33724 It's a bypass kit that says it needs no key, just 1 wire to the computer. Doesn't say PCM or BCM though..
------------------ Bob Williams Multi-colored '87 Mutt, a work in progress! (3800SC installation in super-slow-motion progress... I turn the key and it starts, I turn the key off and it stops. I give it gas and the axles spin. WOOHOO!! It works!! It works!! It works!! Did I mention IT WORKS!?!?)
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11:56 PM
Dec 2nd, 2003
Darth Vader Member
Posts: 388 From: Sullivan, IL Registered: Oct 2002
Before I knew this, I test-fired my car and it ran great. It was very confusing at first, but without the BCM, the PCM doesn't even look for PKIII.
I just checked and the 2000 GTP is different it uses Passkey III and the theft deterrent module sends a fuel enable signal to the PCM, it uses pin 70 C-1 as the input to the PCM. But it’s worth a shoot leaving it unplugged and trying it
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12:19 AM
Mar 22nd, 2004
FordsNeverDie Member
Posts: 952 From: Puyallup, WA Registered: May 2003
The ONLY way that I know of to bypass the Passkey stuff is with West Coast Fiero's Passkey modules. They make them for the Passkey I, II, and III. You just need to specify which year the vehicle is, and Chris will research which Passkey that is if you don't have the info. If you know which one it is, kewl...
Their passkey module will...
A) Fix the crank no start problem... B) Fix the crank and run 30 seconds before dieing problem... C) Fix the way incorrect speedo problem...
They have them on their website at www.westcoastfiero.com under electrical. Check them out if you are still in need of one!
You Don't Know the Power of the Darkside
