I have a 1998 379 peterbilt 3406e cat. The 3 relays the run the fan in the dash.
1st says engine power relay, on terminal 30 it gets power with the key off. With the key on it gets power on 30 & 86 terminals.
2nd says breaksaver/shutdown relay, I get no power key on or off.
3rd one says engine fan relay, I get no power with the key on or off, but with the key on and the manual switch up I get power on terminal 30.
The 4 fuses in the dash. The one 15amp and the one 10amp I get power with the key on. The other two 10amps to the right in the dash, no power with the key on. When manual switch is up I get power on both of them.
Does anyone know what is suppose to have power with the key on, and what is suppose to have power with the key off.
Thanks I appreciate any and all help.