Dashboard lights don't work when headlights turn on...

I know sounds simple but look to the left of the steering column for a rotary swith that goes up and down. This is the dimmer switch that can completely turn down or off what lights are on your display. Forgive me if this is not the case.

Test the headlight switch as follows.

Move your car to a dark area, such as waiting until night or moving to a dark garage, to test your headlight switch.

2Turn on your car, so you can see your dashboard lights. Note whether some of your dashboard lights fail to illuminate.

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Turn on your car's headlights. Note whether your car's headlights illuminate.

4Press the high beam lever to activate your high beams. Note whether your high beams activate.

5Put your car in "Park." Move to the back of the car. Note whether your parking lights are illuminated.

6View any remaining driving lights, such as lights above the license plate. Note whether these lights come on.
If more than one set of lights does not activate when you turn on the lights, you may need to replace your headlight switch. If only one set of lights does not turn on, try replacing the lightbulbs in that set and then retesting your car. If the lights still do not illuminate, you may need to replace your headlight switch.

There is nothign wrong with your car-when you turn on the headlights the car believes you are turnung them on because it is dark outside, so it automatically dims your dashboard lights for you (since it now thinks it's nighttime). Your car already has daytime running lights, so you don't need to turn your headlights on in the daytime-they come on automatically when the car is running. You can keep your dash lights dim or bright by adjusting the small black dial on the left side of the dashboard, whether headlights are on or off if you want to.

i had this happen with my dodge ram 1500. the guy i bought it from put 350 dollar moon lit lights in with leds and they looked impressive but the issue was that they didnt go bright and i could only see 40 feet in front of me and i was sure taping led flashlights would have done me more good that those stupid headlights. then i had the idea of if the brights work and the dims dont then that means no electricity is getting to the dims so i decided to bridge the power from the bright headlight to the dims and it made all four work. now they all work, and only on bright. so im figuring there is a issue with the wiring in the truck. so this is a temporary solution if you really need just plain old lights like i did because i live out in the country

Turn the light switch on and check your tail lights. Back then the tail and dash lights work on the same circuit inside the headlight switch so if one was out so was the other. If this is the case you need a new headlight switch. If not, there should be a fuse in your panel marked "instr". that's for the dash lights. Hope this helps.

Hello


If you have a push/pull type headlight switch just turn the knob clockwise (with the lights on) to brighten the dashboard lighting. It is designed this so that you can control the brightness of the dash in darkness.
Someone might have done some work on the wiring and got things reversed, the only option for you is take it back to the dealer and show them whats wrong and it should be under factory warranty take it to a dealer they may fix it for free.

Check out all your fuses inside cab and under the hood

If your high beams are good you have a faulty switch.

CHECK YOUR HEADLIGHT SWITCH.THE DIMMER IN IT CONTROLS YOUR DASH LIGHT BRIGHTNESS

There is a dash light dimmer control, this controls the dash light brightness only when the headlights are on, check and make sure it is turned on, if it is then replace it, it is defective..