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Finally a cheap passlock fix!
#231
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
#232
please send me the info
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
Can you please send me this diagram
#233
#234
will u please send me a diagram
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
#236
wiring diagram
Hey can you and me the diagram
to slammed9926@gmail.com
to slammed9926@gmail.com
ok first off changing the ignition switch and tumblers will do absolutely nothing sorry if you have already done this. there are three main components to the passlock II system the passlock sensor, the BCM, and the Ecm and of course the wiring in between. Odds are if this keeps happening and there is no other problems such as door locks freaking out trunk release just goin off then it's not the bcm if you do the relearn feature and it works the it is also not the Ecm. so you are left with the 3 wires that run from the bcm to the passlock sensor.odds are the passlock sensor is bad. now there are two solutions either go to the dealer and have the sensor replaced or bypass the system for good. any respectable mobile electonics installer should be able to do this no problem it takes me about 20 mins and i personally charge 40 dollars to do so hope this helps also if you are mechanically inclined in electronics i can send a diagram on how to bypass it yourself hope this all helps
#237
#238
The resistor mod didn't work for us. We tried a DIY setup and also one of the commercial ones that you can buy.
Our "solution" was to install a switch in the yellow lead. Start the truck, then put the switch in the off position. This will bring up the yellow security light on the dash, but no matter. The system is designed such that when a problem is identified while it is running this light comes on but this does not prevent the truck from running and driving as normal. With the switch in the off position the passlock system has no way to know when you've shut down so it holds in this mode of operation indefinitely.
We've been using this for about three months and it has worked as described. Before this, we had to do the relearn once a week or so.
If you lose power - dead or disconnected battery - you will probably have to put the switch in the other position and perform the relearn procedure. Once it's running again, move the switch to the off position and you're good to go until you lose power again.
The security light is annoying (we put tape over it and it's less so) but it sure beats random no-starts and having to perform the relearn procedure randomly.
Another note - Our truck has auto headlights so if it's dark when you do the relearn the headlights are on while the key is on. In the longest relearn procedure you'll be running full lights for 30 minutes or more without the truck running and you may not get through the procedure before you lose power.
Our "solution" was to install a switch in the yellow lead. Start the truck, then put the switch in the off position. This will bring up the yellow security light on the dash, but no matter. The system is designed such that when a problem is identified while it is running this light comes on but this does not prevent the truck from running and driving as normal. With the switch in the off position the passlock system has no way to know when you've shut down so it holds in this mode of operation indefinitely.
We've been using this for about three months and it has worked as described. Before this, we had to do the relearn once a week or so.
If you lose power - dead or disconnected battery - you will probably have to put the switch in the other position and perform the relearn procedure. Once it's running again, move the switch to the off position and you're good to go until you lose power again.
The security light is annoying (we put tape over it and it's less so) but it sure beats random no-starts and having to perform the relearn procedure randomly.
Another note - Our truck has auto headlights so if it's dark when you do the relearn the headlights are on while the key is on. In the longest relearn procedure you'll be running full lights for 30 minutes or more without the truck running and you may not get through the procedure before you lose power.
#239
Have been having this flashing security light issue on and off since 2005 with my 99 suv. Occurs, as with many of others reporting here, at the worst possible time and usually in not so friendly areas.
Earlier in this thread it was mentioned that performance tuning software was out there that may be able to deactivate the firmware that causes the security feature to trigger. Has anyone had success with this option?
If you have, I sure would like to know. Would possibly go that route rather than mess with the mechanical issues, especially in this current cold weather.
My guess dealerships will avoid firmware modifications like a plague. Maybe fed regs or not wanting to admit an issue exists.
Earlier in this thread it was mentioned that performance tuning software was out there that may be able to deactivate the firmware that causes the security feature to trigger. Has anyone had success with this option?
If you have, I sure would like to know. Would possibly go that route rather than mess with the mechanical issues, especially in this current cold weather.
My guess dealerships will avoid firmware modifications like a plague. Maybe fed regs or not wanting to admit an issue exists.
#240
passlock repair, now won't start, no dash lights etc.
Couple of years ago did the contact repair on my wife's 2005 Impala. Worked perfect, easy repair, no problems for 2 years. Today, same problem happened. Started with the security light coming on, then a couple days later, no start...waited about 10 minutes, car starts....blah blah blah.
So I pull out the switch to check the contacts again and yep, 2 blackened contacts. Cleaned them up, reinstalled the switch, now everything is dead.
Checked the battery and connections, Everything clean, looks fine. Battery has 12.48 volts between the battery ends with cables off but only about 4+ volts with cables connected to battery. I figured something I did with the switch. I Pulled the switch back out (luckily I did not put the entire dash pieces back in) to check my work. Again, everything looks fine. Springs seem tight, everything seems to be installed properly...Has this happened to anyone?
A little help would be appreciated if someone knows or has an idea what stupid thing I may have done.
So I pull out the switch to check the contacts again and yep, 2 blackened contacts. Cleaned them up, reinstalled the switch, now everything is dead.
Checked the battery and connections, Everything clean, looks fine. Battery has 12.48 volts between the battery ends with cables off but only about 4+ volts with cables connected to battery. I figured something I did with the switch. I Pulled the switch back out (luckily I did not put the entire dash pieces back in) to check my work. Again, everything looks fine. Springs seem tight, everything seems to be installed properly...Has this happened to anyone?
A little help would be appreciated if someone knows or has an idea what stupid thing I may have done.