Flickering lights is not related. If the battery is nearing the end of its life expectancy, I'd look at that first. It is the key component in helping the voltage regulator maintain proper system voltage. Also check the ground strap between the engine and body, and the smaller negative battery cable that is bolted to the body to be sure they're clean and tight.
You may want to have the charging system load-tested. If the alternator has one bad diode, it will only be able to produce exactly one third of its rated capacity of typically around 90 to 120 amps. Also, "ripple" will be very high. Most professional testers measure ripple. If it is excessive, the voltage regulator will respond to those variations in voltage and try to adjust the alternator's output accordingly. That can result in bouncing voltage levels and flickering lights.
Sunday, January 6th, 2013 AT 4:06 AM