1998 Buick LaSabre,3800 SeriesII


Security light lights while driving, Sometimes goes out by it self, sometimes, stay on until shutdown; no effect on car. During start up, sometimes security lights delays start, times out in about 3 min, sometimes 2 or 3 time outs. Starts after any above combinations, always. Key resistor 1.4-1.5ohms. Outside temp. not a factor. Have tried leaving the key in ignition at shutdown, start up, same random happenings.


The key cylinder itself has been known on these systems to build up resistance internally due to wear and dirt to where the system begins think the key resistance is out of acceptable range (the circuit is through the cylinder mechanicals) and the system won’t start. Sounds like that’s happened to yours.

I’m sorry, but I know of no sure solution other than to replace the cylinder. If it were me I’d try spraying a cleaning solvent in the cylinder first.


I sprayed brake cleaner in the ignition slot. Taked with a friend who suggested an electrical connection cleaner rather than the brake cleaner. Since spraying, I had one incident of a 3 min time out, but since I’ve started the car three more times without any problems. Time will tell. Any comment on using the brake cleaner?


A lot of solvents like carb cleaner or brake cleaner can melt some plastics. But usually if its going to do damage, it does it right away so you are probably ok. In the future, use alcohol or a contact cleaner.


I appreciate the info.
I bought electrical contact cleaner and sprayed a lot into the key switch. Only one not start and a 3 min. time out, and about 9 perfect starts. Had three times during the drive that the security light came on. One stayed on for over 15 min.(ended with normal shut down.) Other light up times were very close to a 5-8 minute run time and they ended between 3-6 minutes. I will try spraying one more time. At least the start up problem appears to have gone away.