Although the BCM is considered the master control module, it has no direct control of engine functions. The ECM determines what actions to take when A PassLock signal, valid or not, is received from the BCM.
9 second passlock bypass, no wires, no tools !!
I´m having this damn passlock problem with my wife´s truck (09 2.9L auto), I just found this video on youtube, and by the comments seems to work fine. I haven´t tried yet but next time our colly does that passlock thing I will try it.
Anyway, I´ll leave this a new post so others can find it quickly.
cheers to all 355 nation members !!!
Anyway, I´ll leave this a new post so others can find it quickly.
cheers to all 355 nation members !!!
21 - 34 of 34 Posts
That is incorrect in regards to the 355.Although the BCM is considered the master control module, it has no direct control of engine functions. The ECM determines what actions to take when A PassLock signal, valid or not, is received from the BCM.
The 355 is one of few platforms the the Starter Signal comes from the BCM.
I had the same issue, it was passlock, the lock blinked on my screen just as described for all other passlock people. It never turned over, never tried to do anything. I replaced the ignition switch, relearned the key, and it's been fine since. Anyone saying that the truck will turn over or it has to be something else is not correct on every model. Mine was an 08, and never turned over.
Not going to argue about the operation of the PassLock System
From the 2006 GM 355 Service Manual. Accept it or not, makes no difference to me:
The Passlock™ system is provided in order to prevent vehicle theft if the ignition lock cylinder is forced to rotate. The Passlock™ controller reads the coded Passlock™ data signal. The data consists of a voltage generated by a voltage divider network created between the Passlock™ assembly and the Passlock™ controller. If the data is correct , indicating rotation of the lock cylinder with the proper mechanically cut key, then the Passlock™ controller sends a password to the powertrain controller via serial data to indicate that fuel should be delivered to the engine. The Passlock™ controller also interfaces with the driver displays subsystem to indicate, via a security telltale, the Passlock™ subsystem status and acute subsystem failures.
The components of the Passlock™ system are as follows:
• The ignition switch
• The body control module (BCM)
• The security indicator on the instrument cluster
• The engine control module (ECM)
Ignition Switch
The ignition switch contains the wiring and electrical switching portion of the column mounted ignition assembly. The ignition switch includes wiring pigtails which connect it to the base of the column connector. The Passlock™ sensor is an internal resistor within the ignition switch.
The ignition switch receives a 5-volt reference from the body control module (BCM) via the ignition key resistor signal circuit. When in the start position, the 5-volt reference travels through the Passlock™ sensor within the ignition switch. This creates a unique voltage value which is returned to the BCM via the off/run/crank voltage circuit.
Body Control Module (BCM)
The body control module (BCM) contains the logic of the theft deterrent system. The BCM provides the 5-volt reference to operate the Passlock™ sensor. The BCM also measures the voltage of the off/run/crank voltage. The voltage measured will indicate whether the Passlock™ sensor has been activated and whether the resistance value from the sensor is a valid value or the tamper value. If voltage measured is in the valid range, the BCM compares this voltage to a previously learned voltage code. If the voltage codes match, the BCM sends a serial data message containing a password to the engine control module (ECM). If the voltage codes do not match, or the voltage is in the tamper range, or there is a circuit fault, the BCM will not send the correct password to the ECM, and the vehicle will not start.
Engine Control Module
The engine control module (ECM) contains the remainder of the logic of the theft deterrent system. If a serial data message containing a valid password is received from the body control module (BCM), the ECM will continue to allow the fuel injectors to operate. The ECM will allow the fuel injectors to operate until it decides there is no valid password coming from the BCM. If the ECM does not receive a serial data message, or receives a serial data message with an incorrect password, the engine will crank and will not run or will start and stall immediately.
From the 2006 GM 355 Service Manual. Accept it or not, makes no difference to me:
The Passlock™ system is provided in order to prevent vehicle theft if the ignition lock cylinder is forced to rotate. The Passlock™ controller reads the coded Passlock™ data signal. The data consists of a voltage generated by a voltage divider network created between the Passlock™ assembly and the Passlock™ controller. If the data is correct , indicating rotation of the lock cylinder with the proper mechanically cut key, then the Passlock™ controller sends a password to the powertrain controller via serial data to indicate that fuel should be delivered to the engine. The Passlock™ controller also interfaces with the driver displays subsystem to indicate, via a security telltale, the Passlock™ subsystem status and acute subsystem failures.
The components of the Passlock™ system are as follows:
• The ignition switch
• The body control module (BCM)
• The security indicator on the instrument cluster
• The engine control module (ECM)
Ignition Switch
The ignition switch contains the wiring and electrical switching portion of the column mounted ignition assembly. The ignition switch includes wiring pigtails which connect it to the base of the column connector. The Passlock™ sensor is an internal resistor within the ignition switch.
The ignition switch receives a 5-volt reference from the body control module (BCM) via the ignition key resistor signal circuit. When in the start position, the 5-volt reference travels through the Passlock™ sensor within the ignition switch. This creates a unique voltage value which is returned to the BCM via the off/run/crank voltage circuit.
Body Control Module (BCM)
The body control module (BCM) contains the logic of the theft deterrent system. The BCM provides the 5-volt reference to operate the Passlock™ sensor. The BCM also measures the voltage of the off/run/crank voltage. The voltage measured will indicate whether the Passlock™ sensor has been activated and whether the resistance value from the sensor is a valid value or the tamper value. If voltage measured is in the valid range, the BCM compares this voltage to a previously learned voltage code. If the voltage codes match, the BCM sends a serial data message containing a password to the engine control module (ECM). If the voltage codes do not match, or the voltage is in the tamper range, or there is a circuit fault, the BCM will not send the correct password to the ECM, and the vehicle will not start.
Engine Control Module
The engine control module (ECM) contains the remainder of the logic of the theft deterrent system. If a serial data message containing a valid password is received from the body control module (BCM), the ECM will continue to allow the fuel injectors to operate. The ECM will allow the fuel injectors to operate until it decides there is no valid password coming from the BCM. If the ECM does not receive a serial data message, or receives a serial data message with an incorrect password, the engine will crank and will not run or will start and stall immediately.
Keep in mind that a defect in the ignition switch can affect more than one circuit. It could have disabled both the PassLock and the start circuit at the same time.I had the same issue, it was passlock, the lock blinked on my screen just as described for all other passlock people. It never turned over, never tried to do anything. I replaced the ignition switch, relearned the key, and it's been fine since. Anyone saying that the truck will turn over or it has to be something else is not correct on every model. Mine was an 08, and never turned over.
If that was the case why would it always start after the 10 minute time out (meaning both the starter and passlock defects were OK the next time after I let the passlock timeout). Also, I never had a starter trigger issue without having the passlock issue (blinking lock on the dashboard). If it was it's own issue it would, in my opinion, had reared it's head at other times as well. Look, I am not trying to argue, I am just trying to let folks know that you can have the no starter engage issue with a bad passlock. I am not the first to see it (the guy on youtube video'd it), and I am guessing I wont be the last. Maybe in other years it wasn't the case? I am not sure, and I don't have the service manuals.Keep in mind that a defect in the ignition switch can affect more than one circuit. It could have disabled both the PassLock and the start circuit at the same time.
I just bought a GMC Canyon 2019 with 13,000 miles 3 days ago. Today I was stranded with my son when my GMC locked me out because of the anti-theft passcode. This was my 3rd day of ownership. I was waiting for my son in front of his school when it locked me out and refused to start. I called my local GMC and they walked me through the 10 minute wait trying to reset the code. After 3 hours the tow truck had to be called. As I am typing this, my truck is sitting in the GMC dealership waiting to be serviced. I will never buy another GMC product. I should have bought that Toyota Tacoma. After 3 days of ownership already thinking of trading it in. The CEO's at GMC really don't care about their customers or their products. Apparently from what I'm reading this has been a problem for years that they have never taken care of. Now I understand what GMC really stands for - Garbage Motor Company.
I get your frustration. However, If you believe that different car manufacturer's treat customers better than others after a vehicle sale I would say no they don't. It's the specific dealership where you find the difference. I hope you get a good resolution to your problem.
Things are a bit confused. fitsector may indeed have a PassLock issue. That hasn't been ruled out. What is being questioned is the subject of the video. The person making the video seems to think that the problem he is experiencing is related directly to the PassLock system, but the fact that the engine will not turn over indicates that the problem is something else. No Passlock problem will prevent the engine from cranking.
If, when cranking the engine, the security light is flashing, that indicates a PassLock problem. The engine may initially start and run until the BCM gets the message to the ECM to deactivate the injectors. Once the ECM has deactivated the injectors, on subsequent starts the engine will still turn over, but no ignition will take place.
There is an Owner's Manual procedure to wait 10 minutes and retry. That will work sometimes.
Re. “…but the fact that the engine will not turn over indicates that the problem is something else.” This is not always going to be be correct. Apparently with some years, the engine will crank and it will not start when you are locked out with the passlock. On my 2009 Hummer H3 the engine would not even turn over. The battery was fine. The red lock icon was flashing. I followed the relearn procedure and the lock icon remained lit steadily, and the vehicle started without issue. it has been starting fine all day today. I expect this problem to return. I will likely end up replacing the passlock sensor. I do not know if my Innova 5610 will reveal any issues. Will likely connect over the weekend in an effort to find out. It does appear that in some instances the only thing that’s shut off is fuel, but there are definitely other instances where there is a no-crank condition as a direct result of the passlock being triggered.Things are a bit confused. fitsector may indeed have a PassLock issue. That hasn't been ruled out. What is being questioned is the subject of the video. The person making the video seems to think that the problem he is experiencing is related directly to the PassLock system, but the fact that the engine will not turn over indicates that the problem is something else. No Passlock problem will prevent the engine from cranking.
If, when cranking the engine, the security light is flashing, that indicates a PassLock problem. The engine may initially start and run until the BCM gets the message to the ECM to deactivate the injectors. Once the ECM has deactivated the injectors, on subsequent starts the engine will still turn over, but no ignition will take place.
There is an Owner's Manual procedure to wait 10 minutes and retry. That will work sometimes.
I'm assuming that you live in Canada. There is no "passlock sensor" in vehicles produced for the US market. Camadian vehicles have a PassKey system.Re. “…but the fact that the engine will not turn over indicates that the problem is something else.” This is not always going to be be correct. Apparently with some years, the engine will crank and it will not start when you are locked out with the passlock. On my 2009 Hummer H3 the engine would not even turn over. The battery was fine. The red lock icon was flashing. I followed the relearn procedure and the lock icon remained lit steadily, and the vehicle started without issue. it has been starting fine all day today. I expect this problem to return. I will likely end up replacing the passlock sensor. I do not know if my Innova 5610 will reveal any issues. Will likely connect over the weekend in an effort to find out. It does appear that in some instances the only thing that’s shut off is fuel, but there are definitely other instances where there is a no-crank condition as a direct result of the passlock being triggered.
I'm assuming that you live in Canada. There is no "passlock sensor" in vehicles produced for the US market. Camadian vehicles have a PassKey system.
I also had passlock problems for years on my 2010 Colorado V8 Z71. The truck would not start, acted like a dead battery; 10 minutes later it would start right up. (Mostly when it was 0 degrees or 100 degrees outside so Wife was Pissed). I had done absolutely everything imaginable to resolve the issue; checked all Grounds, Re-ground the wires on Passenger Fender Well. replaced ignition, replaced HVAC head unit, checked all wires under the dash and down by passenger floor kick panel. Nothing! Grabbing at Straws, I changed out the HVAC Blower Motor. Resolved! Fixed! No more Passlock issues. Go Figure! WTF!Re. “…but the fact that the engine will not turn over indicates that the problem is something else.” This is not always going to be be correct. Apparently with some years, the engine will crank and it will not start when you are locked out with the passlock. On my 2009 Hummer H3 the engine would not even turn over. The battery was fine. The red lock icon was flashing. I followed the relearn procedure and the lock icon remained lit steadily, and the vehicle started without issue. it has been starting fine all day today. I expect this problem to return. I will likely end up replacing the passlock sensor. I do not know if my Innova 5610 will reveal any issues. Will likely connect over the weekend in an effort to find out. It does appear that in some instances the only thing that’s shut off is fuel, but there are definitely other instances where there is a no-crank condition as a direct result of the passlock being triggered.
I replaced the Passlock sensor (purchased on ebay). Issue has gone away. There is a 30 minute reset procedure for truck to learn new sensor.
Omg I've been having some problem for months no way this worksI´m having this damn passlock problem with my wife´s truck (09 2.9L auto), I just found this video on youtube, and by the comments seems to work fine. I haven´t tried yet but next time our colly does that passlock thing I will try it.
Anyway, I´ll leave this a new post so others can find it quickly.
cheers to all 355 nation members !!!
Welcome to the Nation.
If that video doesn't solve your issue, come back and start a new Thread and we will address the problem.
If that video doesn't solve your issue, come back and start a new Thread and we will address the problem.
21 - 34 of 34 Posts
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