Security/no start problem on 02 chevy impala


Dear CarTalk listeners,

I am a happy audience of Car Talk. Since last year, my 2002 impala started to experience the security/no start problem. Most times the car starts fine but sometimes the engine just doesn’t crank and the security light is flashing on the control panel. The no-start problem is so intermittent and every time (three times) the car was at dealership, they just cannot duplicate it.

I searched the internet and it appears this is a common problem on GM cars with Passlock system. It seems to me more like a design fault than a part problem. It is so weird that no people asked the question on Car Talk. Are they not listening to Car Talk?

I decided to take a look by myself and GM Technichal Service Bulleton points to the possible problem on BCM connectors. I can locate the BCM under the dash of driver side but somehow I cannot disconnect the BCM connector. Is there any special tool that is required to disconnect the connectors?

Any suggestions how to fix the problem by DIY?

Many thanks.


There may be a retainer tab on the connector that has to be pressed down in order to remove the connector.


I do see some container tab around the connector and the press-down just doesn’t work. Maybe I should try it again.


Finally I managed to take the BCM off. I noticed a lot of yellow dots on solder points on the BCM board (both in front and back). Please take a look at

Is it possible that the BCM is defective? Your inputs are greatly appreciated.