gary96360

hey i just put leds in the dash today and killed the battery because i left the headlights on ooops. so i jump started it after i put in the leds. the battery light stays on now but its pretty dim. im confused, could it be the led not switching off.

scuba

Did you let the truck run to charge the battery again?

gary96360

yeah ive driven around town so the battery is charged enough. i just started it again and the light is still on, its just dim. the battery needs to be replaced because the battery dies when i leave the lights on for 5 mins. im going to put in the stock bulbs tommorow and see if it goes away

gary96360

when it starts the light is on bright for a sec or two the way its supposed to be then it goes dim

sam333

Did you reverse your leads by accident while jump starting? Usually a dim charge light means you have burned out a diode in your alternator.

myyota

Your alternator is bad, but your also saying the battery is weak, so it would be a good idea to replace both.

xxxtreme22r

if the alternator was bad wouldn't that give him both charge and brake lights?

stupid question, but are you sure one of those LED's is just somehow giving ambient light to the batt light making it look on when it's not?

one way to test this is to take the dash out, pull the bulb from the batt light and see if it still looks on.

gary96360

naww i didnt reverse the leads. but ive noticed the parking brake light is kinda funky ever since it snowed. it stays on until i pull the brake then slam it down a couple times then it goes away. the parking light is on also along with the battery light after the led install. the two lights also flicker when i signal. but i totally drained out the battery yesterday until the radio stopped working so that might have put the light on. i drove back from work today and the lights were gone. the battery guage on the dash has always been at 5/8ths max level, does that mean anything?

scope103

The "charge" light is always connected to the 12v of the Acc. circuit, with the other lead to the alternator. When the alternator is not running, that lead is at ground, so the light illuminates. When the alternator is running, that lead is at 12v (approx) too, so there is no voltage across the bulb and it goes out.

The output of an alternator is not smooth DC, but is full-wave rectified AC. If one (of three) diode fails, every third "hump" is flattened, and the alternator lead is at ground about 1/3 of the time. So the charge light would light dimly.

But LEDs light with much less current than an incandescent bulb. I wonder if there is enough voltage across the LED during the small time between the "humps" of the full-wave rectified output that it will light dimly, where an incandescent bulb would not light at all?

The way to tell is to temporarily put the incandescent bulb back in and see what it does. It may just be that LEDs don't work well as charge lights (because of the dim lighting). OR, the alternator could have one (or all) of the diodes out. To directly check that you need an oscilloscope, but I'd take the easy way out and schlep it down to the store where they'll test it for free.

sam333

Has this LED mod been done before?

xxxtreme22r

yes and I don't remember anyone having problems with it, but all of the ones I can think of are not your gen truck.

jdjesse

I want to do an LED swap for all the lights in my dash and tail lights and hazards, could someone link me? Also it sounds like your alternator is dieing to me

OrRunner

iTrader: (1)

https://www.yotatech.com/search.php

gary96360

i drove the truck during the day and the lights did not show up. i can only see them dimly at night. that probably means light from the other bulbs must shine thru or something. i checked the voltage at battery when the truck cranks, its around 10.6 volts and when the truck is running its at 13.9 volts

gary96360

i stuck in regular bulbs for the parking brake and battery and now the problems gone