Passlock system bypass
rtx042
08-15-2005, 05:24 PM
I have a '96 Grand Am that has been giving intermittent starting problems due to the Passlock theft system. It will reset in 10 minutes with the key in the on position and will normally start the second time.
Because the car has 260,000 km on it the ignition switch is probably worn and in need of replacement. I dont want to spend any more money on this old car so have found a way to bypass the Passlock system. I have started the car over 200 times since this fix and it hasnt failed yet.
Start by removing the plastic cover from the lower steering column to expose the ignition switch. There are 3 Torx head screws that must be removed to get the upper and lower covers off the column.
You will find a 3 wire ribbon cable running from the ignition switch down the column and up under the dash. With the ignition OFF (take the key out to be sure) cut this ribbon cable with diagonal pliers. Now try and start the car. It will turn over and start but will die after 2 seconds because you have severed the communication cable from the switch to the body control unit. With the ignition OFF (key out) you must now bare the ends of these 3 wires and crimp INSULATED male/female connectors on to them. Connect these wires (pay attention to the wire colors because I'm not sure what the results would be if these wires were crossed) Now start the car and WHILE THE ENGINE IS RUNNING disconnect these wires one at a time being careful not to ground out any of them by touching any bare metal. Carefully tape the ends of these connectors so that there is no way for them to contact ground. The car will be running and the THEFT SYSTEM light will remain on in the dash. With the wires taped and disconnected try to start and restart the car. It will start each time because the Passlock key code is held within the body control unit until battery power is disconnected. Keep in mind that if the battery power is lost for any reason the code will clear to zero and you will have to follow this procedure again. I may in the future connect these wires with small dipswitches to speed up the bcu recoding if battery power is lost. I can live with the "theft system" dash light remaining on.........it was a cheap fix and it seems to work!
Because the car has 260,000 km on it the ignition switch is probably worn and in need of replacement. I dont want to spend any more money on this old car so have found a way to bypass the Passlock system. I have started the car over 200 times since this fix and it hasnt failed yet.
Start by removing the plastic cover from the lower steering column to expose the ignition switch. There are 3 Torx head screws that must be removed to get the upper and lower covers off the column.
You will find a 3 wire ribbon cable running from the ignition switch down the column and up under the dash. With the ignition OFF (take the key out to be sure) cut this ribbon cable with diagonal pliers. Now try and start the car. It will turn over and start but will die after 2 seconds because you have severed the communication cable from the switch to the body control unit. With the ignition OFF (key out) you must now bare the ends of these 3 wires and crimp INSULATED male/female connectors on to them. Connect these wires (pay attention to the wire colors because I'm not sure what the results would be if these wires were crossed) Now start the car and WHILE THE ENGINE IS RUNNING disconnect these wires one at a time being careful not to ground out any of them by touching any bare metal. Carefully tape the ends of these connectors so that there is no way for them to contact ground. The car will be running and the THEFT SYSTEM light will remain on in the dash. With the wires taped and disconnected try to start and restart the car. It will start each time because the Passlock key code is held within the body control unit until battery power is disconnected. Keep in mind that if the battery power is lost for any reason the code will clear to zero and you will have to follow this procedure again. I may in the future connect these wires with small dipswitches to speed up the bcu recoding if battery power is lost. I can live with the "theft system" dash light remaining on.........it was a cheap fix and it seems to work!
xeroinfinity
08-16-2005, 10:41 AM
wow rtx thats a lot of work. when all u needed to do is disable the passlock \,,/
rtx042
08-16-2005, 04:28 PM
wow rtx thats a lot of work. when all u needed to do is disable the passlock \,,/
Well, help me out here big guy......do you know an EASIER way?
If so, please share it with us lesser mortals!
Well, help me out here big guy......do you know an EASIER way?
If so, please share it with us lesser mortals!
xeroinfinity
08-16-2005, 06:36 PM
here might have worked, but i guess its not free. i see ur piont. sorrie
http://www.youreq.com/outdooreq/car-electronics/remote-starters/designtech/20402.asp
http://www.youreq.com/outdooreq/car-electronics/remote-starters/designtech/20402.asp
PsychoAm
11-05-2005, 09:38 AM
Is there any other way to disconnect the passlock system?
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