New to me Mack truck

[Phil P 0]

Hello all

This truck belongs to a friend of mine and another friend of mine told him I could fix anything.

Well to get started I need some information.

The truck has an electrical problem in that the headlights will not turn off.

Now before we get into a bunch of ideas as to why this is happing I need some basic information.

Where is the circuit breaker / fuse panel?

Where would I find the relays if this truck is equipped with relays for the heavy loads?

Now just to inform you the driver advises that the headlights stay on even with the headlight switch removed.

Phil P

[hatcity 2,380]

Crazy thought, but do they go out with the parking brake set?

My truck was a 2001, and when you released the park brake, they came on

Guy that bought it from me called one day about ready to tear dash apart

[tjc transport 1,218]

agreed. a lot of these trucks came with daytime running lights. 

if the parking brake is off, the headlights are on.

only thing that will turn them off is pulling the DRL relay.

[Phil P 0]

Hi

A little more information.

This truck has been owned and operated by the same person for several years.

The headlight   issue is of recent origin.

Phil P

 

[Phil P 0]

Hello All

I have now found the fuse and relay panel.
There were also several schematics in this location but nothing that gave me any information on the layout of the fuse / relay panel.

Is there anyone here that has something that would tell me if one of these relays is for the headlights?

Thanks

Phil P