Headlight switch turning on fuel pump? S13 w/SR - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Luvs2slide · 06-04-2008, 12:54 AM

So yea, I turn on my headlight switch (to raise/retract headlights) I can hear my fuel pump prime it self. This is also when there is no key in the car. I'm guessing theres a short somewhere. Any idea if this could possibly be under a the fender harness??? Any suggestions are helpful. Thank you!

GSXRJJordan · 06-04-2008, 01:14 AM

Yup, it's fairly common. You'll also notice that when you turn the car off, with the headlight switch on, it won't turn off - what this means is that the ECU relay (which turns on the ECU, and that tells the fuel pump to prime) is pulling power through your headlight switch.

I've had similar problems a couple times, and traced the problem back to 'pin 5' on the headlight switch - it supplies power to the ambers and parking lights. Somewhere between the headlight switch and the ECU relay (most likely the driver's side fuse box/super multiple junction) something goes awry. I'll update if I ever actually fix the problem (I just cut the wire and supply an ignition-switched +12v to the pin from the ignition switch harness).

Luvs2slide · 06-04-2008, 11:17 AM

(I just cut the wire and supply an ignition-switched +12v to the pin from the ignition switch harness).[/quote]

WHat is the switch used for? I have been having a headlight gremlin for forever and just unplugged the connector for the headlight retractor. So they just stay up all the time.

KiLLeR2001 · 06-04-2008, 01:02 PM

The headlight switch is there simply to have the luxury of keeping your headlights up while not having the lights on. Good to keep them up during the colder months because anyone that has tried to flip their popups during the cold probably at one point had to walk out and do it manually.

Luvs2slide · 06-04-2008, 02:58 PM

I know what the switch is used for. GSXRJordan said he had rigged up a switched for something else which is what I was curious about.

GSXRJJordan · 06-04-2008, 10:05 PM

I'm talking about the headlight switch, meaning the one on the stalk - next to the steering wheel. The 'flip up' switch pulls power through the headlight switch also.

I cut the power to the switch, and wired in ignition-switched +12v (meaning it's got +12v while the ignition is on the "acc or on" position).

06-04-2008, 12:54 AM	#1
Luvs2slide Zilvia FREAK! Join Date: Oct 2006 Location: NW Florida Age: 43 Posts: 1,490 Trader Rating: (81) Feedback Score: 81 reviews	Headlight switch turning on fuel pump? S13 w/SR So yea, I turn on my headlight switch (to raise/retract headlights) I can hear my fuel pump prime it self. This is also when there is no key in the car. I'm guessing theres a short somewhere. Any idea if this could possibly be under a the fender harness??? Any suggestions are helpful. Thank you!

06-04-2008, 01:14 AM	#2
GSXRJJordan Post Whore! Join Date: May 2006 Location: San Diego, CA Posts: 9,135 Trader Rating: (19) Rides Gallery: GSXRJJordan Feedback Score: 19 reviews	Yup, it's fairly common. You'll also notice that when you turn the car off, with the headlight switch on, it won't turn off - what this means is that the ECU relay (which turns on the ECU, and that tells the fuel pump to prime) is pulling power through your headlight switch. I've had similar problems a couple times, and traced the problem back to 'pin 5' on the headlight switch - it supplies power to the ambers and parking lights. Somewhere between the headlight switch and the ECU relay (most likely the driver's side fuse box/super multiple junction) something goes awry. I'll update if I ever actually fix the problem (I just cut the wire and supply an ignition-switched +12v to the pin from the ignition switch harness). __________________ Jordan Innovations has a new web site! www.JordanInnovations.com -- All your favorite FD Pro Drifters love it, trust me -- www.JordanInnovations.com

06-04-2008, 01:02 PM	#4
KiLLeR2001 Post Whore! Join Date: Jun 2007 Location: オーランドフロリダ Posts: 7,955 Trader Rating: (46) Feedback Score: 46 reviews	The headlight switch is there simply to have the luxury of keeping your headlights up while not having the lights on. Good to keep them up during the colder months because anyone that has tried to flip their popups during the cold probably at one point had to walk out and do it manually. __________________

06-04-2008, 10:05 PM	#6
GSXRJJordan Post Whore! Join Date: May 2006 Location: San Diego, CA Posts: 9,135 Trader Rating: (19) Rides Gallery: GSXRJJordan Feedback Score: 19 reviews	I'm talking about the headlight switch, meaning the one on the stalk - next to the steering wheel. The 'flip up' switch pulls power through the headlight switch also. I cut the power to the switch, and wired in ignition-switched +12v (meaning it's got +12v while the ignition is on the "acc or on" position). __________________ Jordan Innovations has a new web site! www.JordanInnovations.com -- All your favorite FD Pro Drifters love it, trust me -- www.JordanInnovations.com

06-04-2008, 11:17 AM	#3
Luvs2slide Zilvia FREAK! Join Date: Oct 2006 Location: NW Florida Age: 43 Posts: 1,490 Trader Rating: (81) Feedback Score: 81 reviews	(I just cut the wire and supply an ignition-switched +12v to the pin from the ignition switch harness).[/quote] WHat is the switch used for? I have been having a headlight gremlin for forever and just unplugged the connector for the headlight retractor. So they just stay up all the time.

06-04-2008, 02:58 PM	#5
Luvs2slide Zilvia FREAK! Join Date: Oct 2006 Location: NW Florida Age: 43 Posts: 1,490 Trader Rating: (81) Feedback Score: 81 reviews	I know what the switch is used for. GSXRJordan said he had rigged up a switched for something else which is what I was curious about.