Where is the horn relay located on a 1978 Chevrolet Blazer K5? I can't find the actual horn either.

Video
https://www.carcarekiosk.com/video/1995_Chevrolet_Blazer_LT_4.3L_V6_(4_Door)/fuse_interior/replace

What fuse does what?

Chevy K5 Blazer & GMC Jimmy (1982-1991) Fuse Box Diagram

https://knigaproavto.ru > shemy > 833-1982-1991-chev...

Fuse Panel Diagram Chevrolet Blazer and GMC Jimmy (K5, K10 & V10; 1982, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, 1991)

Is it possible the replacement engine has a water pump that turns the opposite direction from the original ?
The thermostat has to be open to allow flow thru the radiator, have you tried running without a thermostat to check flow ?

it is underneith a bracket behind the driver side headlight. :)

the horn relay is located behind the glovebox in relay center, the highbeam doesnt have a relay, check the bulbs and also check the highbeam switch located on steering column. hope this helps,

if the horn press in in the middle of wheel then their is a carbon brush under the steering wheel ,then wire runs into loom from around the steering lock area

Sounds very much like a stuck relay. Find the fuse box and then the sarting relay and replace that.

located under the instrument panel to the left of the steering column. The fuse block should be visible from underneath the steering column, near the pedal bracket.


Some models may use an underhood fuse/relay panel


If the panel is not visible, check for a removable compartment door or trim panel which may used on later models to hide the block. This panel is usually located on the left end of the instrument panel.
The convenience center is located just below the instrument panel on the drivers side. It contains individual relays such as the seat belt and ignition key alarm, and flasher.
On newer model vehicles there is an underhood fuse/relay center contains both mini and maxi fuses, as well as some relays.

Replacement The turn signal and hazard flasher units are usually located in the convenience center located just below the instrument panel on the drivers side. Replace the flasher by unplugging the old one and plugging in the new one. Confirm proper flasher operation.

It sounds like a problem with your horn relay or fuse...

When looking for relays, the most common spot is in the relay fuse compartment under the hood, either near the battery OR near the firewall in most instances.

However when troubleshooting any electrical problem, checking all fuses in both the passenger and engine compartment is crucial before moving on.

Use your owners manual or a Haynes or Chilton manual to determine which fuse is resonsible for which circuit or the information is usually located on the inside of either compartment cover

it sounds like you either have a bad solenoid, starter, or either a blown fusible link at the starter.

horn is usually in fender at frt,u may have 1 in each fender.