Can someone help me out to understand why when I press on my brake when my truck is off it activates my fuel pump relay. Some guy break checked me and my boyfriend and now it's doing this it didn't before. Any insight would be greatly appreciated. ( Oh it also turns the radio on and off.)

 

How do you know that the fuel pump relay is getting activated?

What did the guy do to the truck that started this, I am not clear on that?


George

 

We know it's the fuel pump relay starts clicking when we press on the break and what happened was some guy break checked us so we slammed on the breaks and that's when this started happening.

 

Do you have and know how to use a test meter or a test light? If so the first thing we need to do is remove the relay and see if the relay coil +V pin is actually getting energized when you press the brake pedal.

I need year and model.

George

 

It's a 2003 blazer LS I do have a test meter.

 

OK pull the relay and see if the pins are labeled. Not a schematic but the actual pins labeled. The possibilities are 30, 87, 87a, 85, and 86. Then write the socket slots in the fuse/relay block down and label them 10 o'clock, 2 o'clock, 4 o'clock and 8 o'clock along with the labels if they were on the relay. Put your meter on 20V DC scale, negative probe on the battery ground and test each relay socket with the truck off, no brake pedal. Then repeat all 4 while pressing the brake pedal. Then any slot which showed no voltage, put your meter in the lowest ohm scale and measure those again. Report back


George