Howdy! new member here
Ive got a major problem with my 1996 Blazer. Headlights do not work
a little history here on a trip to the desert my headlights stopped working. we had stopped for gas only 15 min from our destination and after exploring the truck stop for a bite to eat we went to leave and being dark I turned on my lights to proceed and nothing.
we spent the night in the parking lot searching youtube for info on my problem.
driving home in daylight i noticed that the lights did go on after pulling up to a store front window.
so this became an intermittent problem
I replaced the switch and no more issue. ( I wish)
then i would notice a clicking sound comming from the glovebox. the home of the headlight relays.
I could switch to high beams and the noise would stop... temporarlly
lately the headlights just plane stopped working.
I have swapped out the relays and still nothing.
i have let a friend use the truck (in the daytime) and he has tried to trace down the problem and still no power to the headlights.
WTF?
any ideas?

 

There are multiple ways that the headlamps get their power and ground so some questions to narrow down your problem:

Did you replace any of : headlamp relay, daytime running lamp module, the headlight switch or the dimmer switch?

Are the headlights dead in the manual on position for both hi and lo beams?

Do you always have daytime running lights and does lo vs hi bean matter here?

Do you have and know how to use a digital multimeter?

 

yes we have replaced the switch on the dash board as this was the cure for our first headlight problem
I know that there is a relay in a box in the glovebox and I can try to see if changing any of these makes a difference
I offered this truck to a friend who has been driving it ( day time only) who has also looked into this situation so I am not totally up on everything that has been tried in order to fix this issue.
Day time running lights go on at the release of the parking break and go off once parked and the parking break is applied.
head lights are non functioning hi and low beams nada nothing
I can check to see if the drl go off if the headlight switch is turned on
I own a digital multi meter but I am not fluent in all of its operations but I am glad to have your attention and I am easy to work with
thank you for your time

 

Do you have sealed beams or composite headlamps (bulbs cab be changed in the assembly). Looks like 96 had both.


George

 

bulbs can be changed in the assembly

 

If we ignore the left high beam for now, the other 3 headlamps are a pretty simple circuit. Since they work in the DRL mode that means that the grounds and bulbs are OK. So lets find out where the loss of +12v is when in manual mode:

With the dashboard headlamp switch in the manual on position and the harness still connected to the back of the switch, what is the voltage on the yellow wire out of the switch?


George

 

so i need to pull the manual switch from the dash board, turn the switch on and read the voltage between the yellow wire and any ground i can reach.
correct ?

 

Yes

George

 

i pulled out all 3 of the relays located in the glove box and tested them and all are functioning properly.
ill test that yellow wire tomorrow morning

 

i pulled out the switch for those headlights and it had some issues so i have replaced the switch....... news flash...... still no headlights....... yellow wire voltage..... ill get that..... fright now its raining and im not into getting soaked....