Lights flashing while driving and doors locking



Help! The lights on my car flashed on my way to work today and the doors kept locking. Even though they were already locked. This whole thing would stop for about 10 seconds and repeat itself again for a minute about 10 times today.


Do you have an aftermarket security system or remote starter installed?


Yes I do. But I haven’t used them in almost a year I’ve just been doing everything manually.


Why haven’t you used them? This could very well be the cause of your problem. If you aren’t going to use an aftermarket system, or if it is not working properly- it needs to be fixed or completely removed. The brains in those things can do all kinds of screwy things like this.


I have seen several instances of aftermarket security systems and remote starters that caused incredible electronic problems as they aged and deteriorated.


I can understand not using the remote starter but why would you not use the alarm system .


The aftermarket alarm was draining my battery so I just stopped using them


Seems like have both systems removed might solve your problems. That would be the simple first step.


However, it will be vital to return the wiring harness to its original configuration, including strain relief and proper insulation to guard against chafing and short-circuiting. Unfortunately, a LOT of installers of these devices have a tendency to butcher the wiring harness during installation.


A door ajar or a failing door ajar switch can cause the dome light to flash on/off and for the doors to re-lock.


An aftermarket alarm may be the problem.

The other thing that could cause this…Is a poor connection at the battery cables, or a battery going dead.
I had this happen to a vehicle that the alternator was not charging tha battery. When the battery got low enough the doors started to lock and unlock.



Good ideas above. Definitely suspect the alarm system as a likely cause. If the headlights are flashing on and off, that could also be a circuit breaker that’s doing it. Caused usually by a short in the wiring harness somewhere. It was a pretty common problem on cars in the 1950’s, you’d see them sitting in the driveway with the4 headlights flashing on and off at about a 5 second interval. The circuit breaker heats up and trips, the lights go out, then the cb automatically resets when it cools off, turns back on, the lights turn on b/c of the short, and the cycle repeats indefinitely. I suppose such a thing could still happen with newer cars.