Electrical issue with sink water pump

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RCN
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Location: New Cumnock Scotland 1.9L Petrol DG Automatic

Electrical issue with sink water pump

Post by RCN »

Hi all
Saw another person here with a pump issue and read his before i opted to ask as my issue is close but not exact. ( i think)
Water pump for drinking supply not working. Pump is in tank under R&R bed and is a 12V feed. Checked for loose connections and found none, went deeper and removed sink for access.
Have 12.4V feed from a junction box which the feed wires go to the leisure battery and mini fuse box with bullet fuses (8A). Checked those, no issue. From the junction box tested voltage to tap and found 12.4V when tap is turned on and 0V when off.
Followed wires behind, down and to wardrobe flooring and found another connection. Tested again. 12.4V with tap on and 0V when turned off
Another section of wire joins this to the pump wires itself. Tested and same readings as above
Disconnected pump and used a battery booster to test. Pump works, in both polarities.
Took pump wires and connected to wardrobe wires. When tested pump did not run.
Is it the pump? I'm confused because it will run directly from the booster pack, but not from a good 12.4V feed.
Electrics are not my strong point and will try again tomorrow after work. Would be good to have working by this weekend
Cheers
all
Just remember. If women don't find you handsome , they should at least find you handy.

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bigherb
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Re: Electrical issue with sink water pump

Post by bigherb »

It is not the pump as you have proved with the jump pack. You have a poor connection in the wiring to the switch, that is why the 12v disappears when you put it under load switching the pump on. You will just have to trace back the wiring and check for loose or corroded connections including the earth connection.
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RCN
Registered user
Posts: 341
Joined: 09 Jun 2011, 07:44
80-90 Mem No: 9776
Location: New Cumnock Scotland 1.9L Petrol DG Automatic

Re: Electrical issue with sink water pump

Post by RCN »

Thanks Herb. Tore into t the other night after work and found a faulty earth like you said. Found it by testing each wire and eeventually rigged up a dummy switch, which worked when current applied. Took tap off and discovered where the nut tightens and holds the tap in place had rubbed THE sheathing off and the wires touched. Hopefully a slder job and some time tonight will set me right
Just remember. If women don't find you handsome , they should at least find you handy.

RCN
Registered user
Posts: 341
Joined: 09 Jun 2011, 07:44
80-90 Mem No: 9776
Location: New Cumnock Scotland 1.9L Petrol DG Automatic

Re: Electrical issue with sink water pump

Post by RCN »

Thanks Herb. Tore into t the other night after work and found a faulty earth like you said. Found it by testing each wire and eeventually rigged up a dummy switch, which worked when current applied. Took tap off and discovered where the nut tightens and holds the tap in place had rubbed THE sheathing off and the wires touched. Hopefully a slder job and some time tonight will set me right
Just remember. If women don't find you handsome , they should at least find you handy.

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