the battery running low on voltage will cause the ampacity to increase.Which will cause the hot wire on your fuel pump to melt the connector.You stated at the beginning that when you travel 45 minutes (multiple brake light usage),When you go down a hill(multiple brake light usage) and when you touch the brake pedal multiple times(multiple brake light usage) your engine fails........It sounds like you have a short in the brake light hot wire start tracing the fault from the brake light switch on the pedal ,disconnect the battery cables ( + and -).Remove both wires from the switch(above the brake peadal) and get a voltage meter that reads ohms/voltage.With 1 lead(probe from the meter) landed on the carriage of the truck land the other lead on the wire test for continuity if you read 12 ohms or higher you should be in good shape.If you read 0.1 to 0.5 you have a dead short since you should be reading thru the brake system lighting circuit.Also visually inspect the wiring connections at the lights and look for melted wiring or breaks most of the time you'll have problem when you replace a bulb and the wire gets smashed like in the rear drivers side boot where your jack is stored.Good luck!Hasta luego!

 

HI !! leester480, Thanks for the explanation ...
On the other hand, I found this information:
"The fuel pump grounds at G402 and there is connected via a splice pack SP423. These locations are for the 4door blazer if yours is 2 door let me know. Near top center of second cross-member from rear, With fuel filler neck ground strap "

I check everything and soon reported...

 

Hi all!
Guys, after 2 years of searching the problem that prompted this post. I have found the problem. is that the insurance company cut the pink wire ignition current number 1 to give a Satellite device. This device has AA batteries that sulfataron and damaged equipment. I request the help I need is this cable from replace to underwood bussed electrical center to connector 12077822. Can tell me where to find the electrical structure (electrical wiring or map) of underwood bussed electrical center (or fusileer)? appreciate your help and sorry for my not so good English language. thanks