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Fass 150 blowing fuses

10K views 13 replies 9 participants last post by  Jhaff 
#1 ·
I replaced both batteries in my truck a little over a week ago. Since then my Fass 150 have been blowing the 10 amp fuse that is on the supplied wiring harness. This never happened in the past. I notice that its blown when I go to start the truck, and just have to replace it once. Today it blew a few fuses immediately. Anyone have any ideas what might cause this?
 
#2 ·
check the fuse connections,my holder went bad and did this,,plus check the pumps ground.
 
#3 ·
You clearly have a short somewhere. I'd start by looking at any wiring for the FASS, especially anything in the fuse box. Then I would look at anything electrical in the aftermarket category. If nothing found, then get wiring diagrams and see what is on that circuit and then find the short.
 
#4 ·
Could it be a bad motor shortening out and blowing the fuse ?
Have you called FASS asking them if this might be the problem or for advice ?
That’s the first thing I would have checked, constantly blowing the fuse.
 
#5 ·
Could it be a bad motor shortening out and blowing the fuse ?

Have you called FASS asking them if this might be the problem or for advice ?

That’s the first thing I would have checked, constantly blowing the fuse.
I know when my AD kept blowing fuses it ended up being a bad motor and they sent me a new one. As soon as I put a new fuse in and turned the key to the run postion a few sexonds later it would pop.

Sent from my VS988 using Tapatalk
 
#6 ·
You have a short in the wiring after the fuse. Either the pump winding are shot (unlikely) or somewhere along the harness the hot wires shorted to ground. Really not much else it could be since its a dedicated fuse for 1 system.
 
#7 ·
This is most likely not the problem but when the water separator needs changing it will cause fuses to blow.
 
#9 ·
I'm bringing this one back from the dead incase anyone else is having a similar issue.

The problem was that there was corrosion inside the plug at the end of the wiring harness, where it connects to the fass itself. The rubber gasket on the wire end of the plug had loosened up and allowed water to get in there. This caused a ton of corrosion inside the plug that I couldn't see just by inspecting the outside of it. Once I took the plug apart this became apparent. I cleaned the inside up, and reattached the female connectors to fresh wire. It seems to be working now. I need to get a new plug to fully trust it, but that appears to be the problem.
 
#14 ·
I'm bringing this one back from the dead incase anyone else is having a similar issue.

The problem was that there was corrosion inside the plug at the end of the wiring harness, where it connects to the fass itself. The rubber gasket on the wire end of the plug had loosened up and allowed water to get in there. This caused a ton of corrosion inside the plug that I couldn't see just by inspecting the outside of it. Once I took the plug apart this became apparent. I cleaned the inside up, and reattached the female connectors to fresh wire. It seems to be working now. I need to get a new plug to fully trust it, but that appears to be the problem.
How did you take the connector apart? I'm having the same shit
 
#10 ·
Thanks for the update, you might want to apply die-electric grease to that connection.
 
#11 ·
Yeah that is a great idea. What I think would be the best course of action would be to remove the outer shell of the plug and fill up the inside with die-electric grease along with the male and female parts.
 
#13 ·
check for corrosion at the ground terminal.look at the fuse holder and make sure the terminals are burnt and have lost their tension for holding the fuse.
 
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