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1992 Buick no crank no start security light is on

I first thought my issue might be the ignition switch or maybe the neutral safety switch but through some knowledgeable help on this site I’ve come to realize that my issue appears to be from the anti theft system. I did a test where I turned key to start and backed off to run and then leave car for 10 minutes. I did this 3 times and it was supposed to go around the security system and then try to start but it didn’t. I went through two trials with the same result. On the first of 3 times in each of the two trials the security light was not on but the 2nd and 3rd times it stayed on. I’ve heard this problem can be nearly impossible to trace and repair. If anyone out there can help me further I would be very grateful.

A bad battery can often confuse systems, have a participating parts store do a free load test and see your cca.

We have a 2 month old battery in the car. Not to say it can’t be bad, I could still check it to be sure. I am keeping a charger on it as I run tests etc… and trying to keep it up over 12V.

Do you have a volt/ohm meter and know how to use it?

On ohms, place your leads at either side of the “pellet” on the key. That pellet is a resistor. Measure the resistance across the key. At the bottom of the steering column locate a small 2 -wire connector, the wires will be white and be wrapped in an orange shroud. Unplug the connector and place your ohmmeter leads to the wires that run up the column, they end at the ignition cylinder. With the key in the ignition, make sure you have the same resistance value through all the travel of the cylinder. This will prove out/condemn continuity through the cylinder and wires.

Ok, awesome, thanks. The key was 2.75 k ohms. Except for one plug labeled air bag, all of the wires coming down the column seem to go into one giant plug. This thing must have 50 connections I can’t count that high. I did spot an orange wire going into the plug and it covered 2 very small gauge white wires so I assumed this to be it. I couldn’t see how to disconnect the wires from this large plug but I found a shrink tube joint between key and large plug and cut it open. This may not be the same since I didn’t disconnect them from down stream. I placed the leads on the soldered joints and with the key in ignition it read 0 ohms. Let me know if this is a valid test. Thanks for your help.

Go online and look up an ignition cylinder for your car and look at the picture. You’ll see how it’s supposed to work. If you don’t have the key resistance at the end of the 2 small white wires you have a problem. Those wires flex every time the key is turned.

0 ohms? Something is still connected. You’re going to have to test this part of the system with the wires disconnected.

The large plug had a hex screw in the center so got it pulled apart. However I can’t get a consistent reading on the wires. I don’t have clips on my meter just probe ends so hard to get on the wires without a finger on each one which I believe gives a false reading is that right? With fingers holding wires on probes it moves around from 1.2 M ohm to as much as 1.8 M ohm. There were times when I was able to get probes to settle on wires without my fingers for a solid connection but it would just show OL except for the occasional bouncing around.

The reading with my fingers holding wires was my own resistance. The OL is telling me there isn’t a complete circuit. One of those 2 little wires must be broken so it’s time to get into the lock cylinder. I appreciate your help.

OK good luck. It’s not that hard to get the lock cylinder out, but you’ll need a steering wheel puller.

Tip: It’s a pain to thread the new wires through the column to the connectors at the bottom. Once you’re sure you’re replacing the cylinder cut the wires at the old cylinder, tape the bottom ends of the new wires to the old, and pull them down through the column.

You will also need to have your new cylinder rekeyed to match your existing keys, or have new keys made that match the resistance of your old key.

I got into the steering column and sure enough a wire was broken on the lock cylinder. When I called the locksmith about new keys I learned a few things. He told me that I just need a resister in the circuit to imitate the key. I tried it out with my second set of keys. I cut the wires below the steering column and taped each wire to either side of the chip on the key and was able to start the car with the other key. Easy way to start car when this happens if you have extra keys and tape, at least a way to get the car back home and not be stranded or pull the car home. Then I was able to buy the resistor that matched my keys and get it wired in. I just put my old lock cylinder back in and my total bill was $4 for a resistor. Of course this bypasses the security but in a car this old I’m ok with that. He also commented on the process that I tried with the 3 ten minute intervals that I could pass on to you if you like. This guy was very nice to share this info with me, he could have just gone ahead and made me keys and made more money.

There are videos on youtube showing people bypassing the key by adding resistors. This is a very common problem with the GM passlock security system.