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.
Good Day Sparky,
Update: 1-29-13
I checked for a draw, but not at any length; in this instance I didn’t see anything.
The battery was in fact weak, and I replaced it (still under warranty); however, that didn’t change anything.
Since we’re heading to the finish line, meaning I’m going to an appropriate shop to get some codes pulled, I thought I would try the “resistor by-pass” as done by so many with success . . . unfortunately that wasn’t me.
I put a 2.2k ohm resistor between the appropriate (cut) wires off the sensor, praying that the car wouldn’t start so I could perform the “relearn procedure” and sadly–no luck! Car started right up, and still have the same problems.
A couple of days later, I disconnected the yellow wire altogether (with the engine running) and that didn’t do anything either.
Finally just minutes ago, I put a different resistor on (different value, slightly higher) and that didn’t do anything either . . . so with everything I’ve done, cleaned, replaced etc., it seems to be narrowing down to the “BCM.”
I have a couple of shops I’m going to call to get a price on a diagnosis (pull some codes), and and assuming it’s the BCM what they will charge to “program” the unit.
Thanks for all your help and any “closing thoughts” would be greatly appreciated.
Cheers,
Frank
P.S. The stock BCM is a Motorola; what brand do you recommend to replace it, and are there any I should avoid?
The only viable testing, that I can see to be done, is in relation to the dead battery condition. If you have a multimeter, I suggest configuring it for reading DC amps and connect it between the negative battery terminal and the negative battery cable. Do not turn the ignition on or any other heavy load as it will blow the internal fuse in the meter. Allow the vehicle to sit untouched for at least an hour. What is the amperage draw reading?
Update:
This morning (1-20-13) I took my wife to work and although the security light was on (solid) the battery light & accompanying chime wasn’t present . . . at least initially. Drove a few miles and it returned.
On a side-note, the door locks are back to normal (and the previously mentioned door chime without key in ignition) after reinstalling the original lock cylinder.
Cheers,
Frank
Sparky,
First, let me reiterate that I really appreciate your input, and hopefully at the end of the day, my experience will add to your collective, and be beneficial to you, me and anyone else that experiences these problems (which I’m beginning to understand is many).
Update:
Since my lastest post I have reinstalled the original “key/cylinder” since the (new) replacement not only “didn’t” fix the problem, but seemed to add other symptoms (door lock issues, chimes etc).
Additionally, today I pulled the BCM out and opened it up and checked for continuity between the pins and board, as well as checked for cold solder joints–all checked out. Also inspected the pins in the (male) plugs which (visually) seemed to be OK (not corroded, bent etc).
Someone else that experienced the same symptoms said they “cleaned the BCM fuses” and that fixed their problems, so I thought “what the hell!” I’ve tried everything else. When I started pulling fuses (with needle nose pliers), they were in fact kind of “stuck”; certainly not easy to pull out. After I got them out, they resembled the contacts from the original (female) ignition switch I cleaned (and later replaced with a new one) i.e., they were very dirty, black etc.
I realize I’m shooting in the dark without knowing the codes, as I was confident I could resolve the problem without spending a whole lot of money ( I have racked up a bill in parts, but all my labor).
As we speak (and all along) when I pull the +bat post off and ground it out it seems to reset the BCM and all is OK for a short time.
When I do the a fore mentioned procedure, I check it (while under the hood) by “testing the remote door lock” via the key pad. I know when the door locks work that, the flashing security light, et al is off.
FYI: The battery has died at least twice since since this all started, which before getting educated on the passlock – BCM nightmare I presumed was a “low voltage” and or battery problem.
Once again, any input is greatly appreciated.
Cheers,
Frank
Yes, I did receive them and was mulling over the situation in order to choice a diagnostic path. I missed the fact that you were not having a cranking issue. In the end the parts replacement would have been the same since the ignition switch replacement would have been recommended. I also strongly recommend changing the lock cylinder at the same time to prevent other problems. Now back to the matter at hand. Have all fuses been checked to make sure they are good and none are Missing? If nothing is wrong with the fuses, we will be looking at a communication problem within or between modules. A Tech 2 scan tool will be needed to diagnose the problem, along with a high skill set. From the information given in your second comment on the 14th, there is a very small chance that a door ajar switch is not working properly and the BCM is being told that the door is open when it is not. However, you need a scan tool to see this data.