Just bought a 1989 s10 blazer. One
problem...headlights don't work. Fuse is
good. All other lights work too. Well,except
the left turn signal also. Any bit of info would
Start by checking for voltage at the headlight socket to isolate problem. If there's voltage present, replace lamp. If no voltage present, check light switch, if voltage ok going in but nothing out of the switch, replace switch, if no voltage present going to swtch, trace back to fuse box. Good luck
It the head light do not work on high and low beams. First look at obvious. Make sure both bulbs are good. If they are good. Both head lights share a ground that is connected to sheet metal on, I believe the left side close to the left head light. Make sure this is good. The connection is names G104 in Aldata
It is located at the front left hand corner of engine compartment. Maybe try to add at jumper wire to grown for testing at terminal 150 of head lamp connector. This will be the black wire. Their should be a green wire and a tan wire that supply the two powers for high and low beam at the left head lamp connector
The headlights have fuses for hi and fuses for low beam. Some models have 1 fuse per headlamp.