What causes a fuel pump to short out?

The fuel pump is responsible for delivering fuel from the gas tank to the engine. The three most common causes of fuel pump failure include: Fuel contamination: Fuel is jeopardized from corrosion, debris and moisture, which can all bring visible contaminants into the tank.

What causes the fuse to blow on a fuel pump?

I would start at the fuel pump itself. If the fuse blows as soon as you turn on the key, undo the connector at the tank to the pump and put in a new fuse. Try it again, if the fuse pops then your short is before that point likely a chafed wire on the body. If the fuse stays good then the problem is in the pump harness or the fuel pump itself.

What causes fuel pump to draw more current than intended?

There is also the possibility of a physical (mechanical) restriction in the fuel pump tubing, filter and/or pick up causing the motor to overload and draw more current than intended. That’s why you should measure the actual current draw of the pump in normal operation to rule that out.

Can a fuel pump overload cause a problem?

If not, check the other loads on the fuel pump circuit as those other loads could be causing the problem (the overload). To check that refer to wiring diagram in Factory Service Manual.

What to do if fuel pump fuse keeps blowing?

You can use a volt ohmmeter to measure the current draw of the pump and see if it is within factory specified limits.

If not, check the other loads on the fuel pump circuit as those other loads could be causing the problem (the overload). To check that refer to wiring diagram in Factory Service Manual.

There is also the possibility of a physical (mechanical) restriction in the fuel pump tubing, filter and/or pick up causing the motor to overload and draw more current than intended. That’s why you should measure the actual current draw of the pump in normal operation to rule that out.