2003 Buick Century dies when left turn signal is used in the dark/ right blinker stuck

Question

I have a 2003 Buick Century. This car has automatic headlights

The Automatic Headlights turn on all lights front and rear and headlamps starting at twilight or on a dark cloudy day and definitely at night. When the automatic headlights come on, as I start my car, my right blinker stays solid, and won't flicker if I push my turn signal to the right. It just stays stuck either way.

The problem has gotten worse, now when I use the left turn signal, my car loses power. the dashboard lights all the way up then the whole car dies. These problems both only occur when it is dark out so it has to be linked to the automatic headlights.

Not sure how to fix or determine what the problem is.

I replaced my battery with a new one last week my last battery was "bad" according to autozone although I just got in in November. Something must be killing/vamping my battery and I feel like it is linked to the problems I am having.

Today I replaced my combination flasher relay thinking it would unstick my blinker, I parked in my garage and once my car detected the lack of light, the right blinker became stuck and I hit my left turn signal and my car died so nothing was solved.

Answer 1

You can try to look for a battery drain as shown in this video by Scotty Kilmer. If you find any drain in the battery you can fix it and this may solve to whole problem.

EDIT: In the video Scotty uses a test light (that you can buy in AutoZone for about $10) or a 1 Ohm resistor rated at 10 Watts and a voltmeter (In case you have one lying around, otherwise those cost around $20 or more) to check if there is any current passing through the battery when the car is turned off. Disconnect the negative terminal of the battery and connect it to one end of the test light or the resistor and the other end to the battery. If you are using the resistor, also connect the voltmeter probes in parallel with the resistor. If the test light turns on or the voltmeter is measuring anything above 1 Volt so you probably have a drain. In this is happening you can proceed to the next part of the diagnosis. Remove one fuse at a time from the fuse box and check if the test light turns off or if the voltmeter shows less than 1 Volt then place it back. If removing one of the fuses can reduce the voltmeter reading significantly, you can check only the system that is protected by this fuse, thus you can find the source of the drain more easily.

Answer 2

This problem sounds more like a bad connection somewhere. When the lights are turned on, the current drawn by the lights is causing a drop in voltage across a bad connection.

It won't be the connections to the battery, because you will have been experiencing problems starting.

I would start in the fuse box by checking the voltages on the fuses to see if any of them have less than 12v on them when the lights are on.

You could try disconnecting the headlight bulbs to help confirm this is the cause. If the problem still persists with the bulbs disconnected, then maybe it is not a bad power connection.

After that I would be checking the voltage supply to each of the electronic control modules, especially the body control module and the engine control module while the bulbs are lit. If the voltage is low to the modules, this would confirm a bad connection.

Answer 3

My guess would be a missing or damaged ground somewhere given the age of the vehicle. Since the car appears to start ok it is most likely the one from the battery to the chassis, and not the one from the battery to the engine block. Examine the wiring around the battery for signs of damage or corrosion. Does the stall behavior occur with the right headlamp assembly disconnected? Examine the wiring near the right hand headlight, working your way back alone the harness to the underhood distribution block looking for ground connections that may be disconnected or damaged. If you can replicate the problem easily in the garage try attaching a jumper wire from the battery negative terminal to a metal screw or bolt near the right headlight.