Pump is always on

junkboy · 03-23-2008

I have a basic kit on my Jetta 1.8t. I fellowed the direction to wired my w/m into my car but the pump will come on when i turn the car on. i know i have the wiring is all correct because i did it twice and double check everything. i don't understand why the pump is always on when the car is running.

dvldoc · 03-23-2008

If it is on when you turn on the key then you do not have it wired correctly. The pressure switch is what is used to complete the ground when you hit the set point and that turns on your pump. You should be hooked up to the top 2 terminals on the pressure switch only.

COM and NO (normally open circuit) If it is wired correctly there should be no way for power to go to a ungrounded pump. 85 on your relay should go to the NO on the switch and the COM should go to a body ground.

junkboy · 03-23-2008

i have it correctly wired to the hobb switch. i did make a bracket for the hobb switch so it would mount on the chassic. would that ground the system?

dvldoc · 03-23-2008

No because the microswitch sealed from the body of the pressure switch. Get a test light and check the leads to the switch. Check it in both NO and NC modes to see it it is still grounded. We have never had a bad pressure switch but i guess it's possible for the microswitch to have been damaged. If you get no resolve send the switch back with your proof of purchase and we will replace it. If it still does it then you know it is wired wrong some where. I would still check all my leads from the relay with the test light.

junkboy · 03-23-2008

alright. i will check tomorrow with a multimeter to see. thank you

junkboy · 03-24-2008

i got it running. i found out the problem. the microswitch was pushed all the way down on the turn knob for the boost. i don't know how that moved. anyways, thanks for the help.

03-23-2008	#1 (permalink)
junkboy Water Injection Newb Year: 2003 Make: VW Model: Jetta Join Date: Nov 2007 Posts: 5	Pump is always on I have a basic kit on my Jetta 1.8t. I fellowed the direction to wired my w/m into my car but the pump will come on when i turn the car on. i know i have the wiring is all correct because i did it twice and double check everything. i don't understand why the pump is always on when the car is running.

03-23-2008	#2 (permalink)
dvldoc DevilsOwn Staff Join Date: Apr 2005 Posts: 1,973	Re: Pump is always on If it is on when you turn on the key then you do not have it wired correctly. The pressure switch is what is used to complete the ground when you hit the set point and that turns on your pump. You should be hooked up to the top 2 terminals on the pressure switch only. COM and NO (normally open circuit) If it is wired correctly there should be no way for power to go to a ungrounded pump. 85 on your relay should go to the NO on the switch and the COM should go to a body ground. __________________ Currently deployed to Ramadi 1 battalion 12th Marines see you in 8 months.

03-23-2008	#3 (permalink)
junkboy Water Injection Newb Year: 2003 Make: VW Model: Jetta Join Date: Nov 2007 Posts: 5	Re: Pump is always on i have it correctly wired to the hobb switch. i did make a bracket for the hobb switch so it would mount on the chassic. would that ground the system?

03-23-2008	#4 (permalink)
dvldoc DevilsOwn Staff Join Date: Apr 2005 Posts: 1,973	Re: Pump is always on No because the microswitch sealed from the body of the pressure switch. Get a test light and check the leads to the switch. Check it in both NO and NC modes to see it it is still grounded. We have never had a bad pressure switch but i guess it's possible for the microswitch to have been damaged. If you get no resolve send the switch back with your proof of purchase and we will replace it. If it still does it then you know it is wired wrong some where. I would still check all my leads from the relay with the test light. __________________ Currently deployed to Ramadi 1 battalion 12th Marines see you in 8 months.

03-23-2008	#5 (permalink)
junkboy Water Injection Newb Year: 2003 Make: VW Model: Jetta Join Date: Nov 2007 Posts: 5	Re: Pump is always on alright. i will check tomorrow with a multimeter to see. thank you

03-24-2008	#6 (permalink)
junkboy Water Injection Newb Year: 2003 Make: VW Model: Jetta Join Date: Nov 2007 Posts: 5	Re: Pump is always on i got it running. i found out the problem. the microswitch was pushed all the way down on the turn knob for the boost. i don't know how that moved. anyways, thanks for the help.