I have a 91 chevy s10 4.3 i had the truck running soon as i cut on the ac. The truck cut off there were no lights no nothing so i check the emcb fuse it was fine please help

SOURCE: 1991 S10 blazer tail lights dont work

i own a 1991 chevy blazer myself but my problem is opposet of yours my back lights stay on well i went underneath the dash board an i look up underneath my steering column an i saw to components one was to my cruise control an the one in back of it was to my back lights an i moved this around an to my surprise my light swork good now but now my speed odometer doesnt not work an my gas gauge am my oil aa water gauge my power windows dont work an niether my a/c or heater defroster im jus wondering if i need to move this component alittke more to the left or right yesterday everything worked hmmmm

SOURCE: running lights stop working 2002 dodge ram

This happened on my '05 2500 Dodge diesel last winter.After spending a full day checking wiring,fuses,relays and the headlight switch I determined the problem was with the (FCU) the front control unit which is mounted with 4 screws to the outward side of the fuse box.When i asked the dealer if they had one in stock they said they usually kept 6 on the shelf,so I figured if they stock this many then they must be a common problem.This unit cost a bit over $300.00. When i installed it I still had no front or rear park/running lights so I started to remount the fuse box and look for another problem and BINGO I felt the relay click and the lights came on,now I'm thinking did this unit need a few seconds to reset or was this just a flukie fix.Well the lights worked fine for 3 months and the same problem happened again.This time I installed my old FCU just to see if the new one went bad but still no lights,but as I was moving the fuse box around again I felt/heard the relay click and the lights came on.

So I took the fuse box out of the truck and completly dismantled it (dealer says a new one costs $700.00).These boxes snap together and then there are 3 points where the plastic is melted (studs) and these need to be drilled out to separate the top and bottom halves,then the box is easy to take apart.There is a printed circuit board inside that the FCU plugs into with about 40 small connectors and there is where the problem was.One of the lead circuits on the board had corroded and lost connection.I just soldered in a piece of jumper wire and that cured my problem although this probably could be repaired properly by someone with circuit board experience I was happy with my mickey mouse repair for now.

This may sound complicated but the fuse box can be removed from the truck in 10 minutes(honestly) it took me longer to make a sketch of the harness plug in locations than it did to remove the fuse box.Once you have the box out it takes about 20 minutes to drill the (3) plastic studs and split the top and bottom sections (there are no springs on ball bearings or other surprises to fly out as you separate the 2 parts) then if you don't feel you have the skills to check the board and do the repairs you can have an electronics shop do an inspection.

A couple of things that puzzled me while trying to find this problem was that the dash lights still worked,the chime that rings to tell you you have left your lights on still chimed even with only the park lights on,and there was no power at both park light fuses.

When i found out the price of these fuse boxes I automatically thought I'd get one cheap at the local junk yard..big surprise,they said they can't find enough of them to keep up with the demand and also said they often get calls from people saying that their fuse box burned up,so appearently there is a problem with dodge truck fuse boxes!! When I questioned the service manager at my dodge dealer about these things going bad he agreed and said they have replaced many of them.

Hope this helps and I didn't scare you too bad.

Randy in Nova Scotia

SOURCE: My 2004 F-150 Ford Truck will not engage into 4 wheel drive low.

I am going to ask a dumb question....do you have it in neutral and the brake mashed when you switch to 4WD LOW? I believe that is what my book says to do.

SOURCE: 2005 chevy silverado 1500 v6 the heater and ac quit working

your speed switch located in heater box usually one wire to it in passenger feet area above "TOES" usually you loose 1 or 2 speeds on fan but it is unplugged or completely cooked good luck!

SOURCE: parking lights on a 91 chevy 1/2 ton pick up truck

I had the opposite problem on a 92 and 94 chevy trucks.I had park lights but no headlights and both were solved with switch itself.