This car has an intermittent no start condition with the security light flashing. Checked codes and found code B2960 stored. The code is for a valid but incorrect passkey signal. Now there are several different things that can cause this code but the most common is a failing passkey sensor which is part of the ignition tumbler kit. Some of the others are a faulty Ignition Switch, Body Control Computer and poor connections in the wiring harness. Because this problem is usually so intermittent there is not much real testing you can do that will result in a clear answer. I have found the only practical thing to do is to look at passkey voltage with a Tech 2 and gently wiggle the wiring some at the ignition switch and the BCM to see if there is any problem with the harness. Also look at passkey voltage while switching the key off and on. It should be about 5 volts when you initially switch the key on and then drop to a value higher than 0 and lower than 5 volts. Normally I see anywhere from .78 to 3.9 volts. If I see no other problems I always change the ignition tumbler kit and install a new ignition switch as well. If one is failing the other will not be far behind. I have seen plenty of these ignition switches fail without a passkey fault so I replace both as a rule.
With that out of the way this is the what you have to do to change the switch. Drop the tilt steering column to the full tilt down position. Remove both of the dash end caps and remove a screw from each end. Start pulling the trim panel from either end until the clips release. If it does not seem to want to release check for any extra screws that may be retaining the panel. If none are found pull harder but please be careful as panels can break.
After the trim panel is released you will have to disconnect the switches. The hazard switch needs the center tab depressed while you pull the harness connector from the switch.
The Traction control switch needs the center tab lifted slightly while the harness connector is pulled from the switch.
You will also need to remove the lower panels. There and a coulpe of retaining screws and a retaining pin or two. After all retainers are removed pull the cover towards the driver’s seat.
Disconnect the trunk release switch if present and now you will find a metal panel.
Remove the attaching screws and place aside.
Next you will need to remove the two 10mm headed screws that hold the switch assembly to the dash.
Next pull the switch down through the opening in the bottom of the dash.
With the key off release the locking tabs and pull the two main harnesses from the ignition switch. Make sure the key is off, it will save programming time.
Next turn the key on and depress the locking tab for the shifter interlock cable and pull the cable out of the switch.
Next depress the metal locking pin that hold the tumbler and sensor assembly into the ignition switch, rotate the key and pull the assembly out of the ignition switch.
Disconnect the sensor wiring harness by depressing the two side locking tabs and pull from the switch.
Install the new ignition switch and then install the new tumbler and sensor assembly.
I have another post for assembly of the tumbler kit. Please click here to see that post.
After the ignition switch and tumbler assembly are back together turn the key on and reinstall the shifter interlock cable. Then Make Sure The Key Is Off and Then Connect The Two Main Harness Connectors. Again this saves programming or relearn time. Now attempt to start the engine. Do Not be surprised if it does not start. Leave The Key ON and Wait about ten minutes or until the security light stops flashing. You may have to repeat this process up to four times in all before the system will relearn the new sensor value. The closer the new sensor value is to the original the quicker it will relearn. On some rare occasions you will have to use a Tech 2 and reprogramming software to teach the system the new value.
I have a 1999 Cavalier that has simular issues. It dies, and when I try to restart it the “antitheft” light comes on and never blinks. and of course will not start. I have done the relearn procedure which sometimes helps, but not always. I have tested terminal 2 in the ALDL and there is no voltage at any position of the key. There is no codes on any module. I hope that you can help me with what may be causing this problem. Thanks
Thank you, Sparky – you were exactly right! Apparently my multiple attempts at the relearn procedure yesterday worked; I had just run my battery down. A quick charge and then attempting to start while still connected to the battery charger was the ticket. Thanks again; I really appreciate your knowledge!
The ‘weirdness” could be explained by a low battery condition. It is paramount that adequate battery voltage is maintained during the relearn process. I recommend keeping a battery charger on the battery.
On the Impala’s the security light will not go out during the relearn process. Since the security light is part of the “driver information center” panel within the instrument cluster, the panel will display each warning (battery, security & etc) once. This is not considered flashing. When in the relearn process the light will flash twice during the ten minute cycle. After the ten minute cycle is complete it will only come on once. This indicates that the ignition can be turned off for 10 to 30 seconds and then the key can be switched to the crank position again. This gets you to the second cycle in the relearn process that may have to be repeated up to the fourth time when the engine will start. On a very rare occasion the BCM will have to be commanded to do a theft relearn with a Tech 2 scan tool and GM Tis2Web programming software.
I just had a mechanic replace the ignition switch and cylinder in my 2001 Impala because of passlock issues. When I was doing the first cycle of the relearn procedure, the security light would not go off (waited about 25 minutes). I turned the key to off and tried again with the same result. Once again I tried and the light finally went off so I started the second cycle, but the light wouldn’t go off again. This is the weird part and hard to explain. The instrument Pavel is now cycling through various trouble messages for problems that don’t exist (low fuel, service vehicle soon, low coolant level, etc.) Along with the battery and security lights. Also, the car is makes a noise like it is gettting electricity, then the flow is stopped and then starts again. It did this so many times in succession while I was trying a cycle of the relearn procedure (and not sitting in the car to notice) that my battery is now low. When this happened while sitting in the car, I started pulling fuses to see if it would stop. It stopped when I pulled one of the BCM fuses. I had the BCM replaced about 7 years again and haven’t had any issues until the ignition switch was replaced. I disconnected my battery as a “just in case” because this weirdness also happened when my key was out of the ignition. Any ideas?
Hi Sparky,
The trunk light was out and I’ve replaced it. Will give it a day or two and see what happens.
I don’t recall what scanner the mechanic was using at the shop my wife recently went to.
Thanks,
Frank