Jump to content
SAU Community

Recommended Posts

Hi ppls,

A little while ago I ran a direct volt feed to my fuel pump.

I used a Jaycar 60amp relay.

My usual routine is to turn the key to the on positon, wait for the fuel pump to raise fuel pressure then auto turn off, I then start the car.

Occasionally the fuel pump stays on and keeps priming and priming and priming. :O

The only way to stop it is to pull the earth from the relay.

Is it possible the relay is some how getting stuck?

I run the std fuel pump volt feed through the relay then straight to the chassis as its earth.

Could this be the problem? Kind of like connecting a negative and positive without anything inbetween using some power?!? big sparks and not good. :O

I'm not that electrically minded so I really am not sure where to start looking?!?

Edited by Cubes
Link to comment
https://www.sau.com.au/forums/topic/95019-relays/
Share on other sites

Cubes, if you have a look inside a relay, it's a very simple device. It's unlikely that it will get stuck open. Relays do not need much power at all to trigger. Your ecu might still be supplying a small amount of power after priming is finished.

My advice would be to change the relay anyway, in the rare case that it is faulty. They're cheap anyway.

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1717982
Share on other sites

Space Ghost...

Great idea.. I'll give that a shot.. lol So simple.. :O

Next time it does it, I'll jump out with my trusty multimeter and measure the volts running from the ecu.

If it is small amounts as the MANWHORE has suggested then its resistor time.

If not, new relay. :O

Edited by Cubes
Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1718019
Share on other sites

90% of the time the relay works as its should.

Only occasionally it locks on, unsure if thats still possible with a fused relay?

I also observed the relay tends to leak voltage.. The constant feed from the battery see's 0.02v, even with the trigger feeds disconnected.

Edited by Cubes
Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1718057
Share on other sites

I've seen them stick on and I've seem them fuse together but the latter is permanent.

It might just be the ECU though. Mine does a similar thing and it is wired in the stock manner. I didn't notice that it stayed on sometimes until I put a GTR fuel pump in because I couldn't hear it before but now I can.

When I say similar... without the engine on it only primes for about 2-3 seconds but it's when it's started that it can go on and on or not depending on it's mood.

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1719740
Share on other sites

i too have since similar results since putting a bnr33 pump in my gtst + powerfc. normally when it first starts the pump runs flat out even at idle, sometimes the only way to make it stop is to tap the accel pedal and the revs jump a tiny bit then back down again and the pump goes off

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1720586
Share on other sites

Interestering...

Since I fitted the AP PowerFC the fuel pump constantly runs on high, prior it would run on low at idle then once you touch the accelerator it would run on high.

All though prior to the wiring mod I never had it get stuck on while priming.. Only since after the wiring mod.

Which makes me suspect the relay, or a small amount of voltage still passing that is activating the relay.

The wiring mod was definitely worth wile.. Its much louder as it sounds like its spinning so much harder, it also no longer vibrates the floor pan causing it to be noisy in the car. Now you can only hear the buzz/surge/bubble or what ever type sound it is from the outside once the fuel gets really warm on a hot day with little airflow movement.

Edited by Cubes
Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1720608
Share on other sites

It should be setup something like this.

85 (-12V GND from ECU fuel pump terminal)

86 (+12V IGN switched)

87 (+12V to the fuel pump terminal)

30 (+12V supply from battery with fuse/fusable link)

So what will happen is, when the ecu switches the pump on (nissan usually ground relay for pump) it switches the low current coil in the relay, allowing high current from battery from pin 30 on the relay through to terminal pin 87 into the pump.

when the ecu turns the pump off (opens pin 85) the relay will open and stop pumping fuel.

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1721951
Share on other sites

you need to get a diode protected relay or install a diode in the earth wire on the relay that will stop the relay from engaging they require milli amps to engage thats the beauty of a relay little current to trigger put a relay on it and woohoo your fixed unless your relay is shgged in the contacts catchya !

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1724906
Share on other sites

I hope you sort out your electrical gremlins ASAP.

The idea of the pump time out is in case of accident, you don't want fuel pumping everywhere even though the engine may have stopped.

If you've had an engine fire fed on 50psi fuel, you'd have the fear believe me.

Regards.

Indeed, the thought is scary. :P

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1725137
Share on other sites

60amp is a big relay for a fuel pump. The 044's only pull about 15-20amps max.I'm running a 40amp on mine as i had one lying around.

I've noticed that the bigger amp fuses (EDIT Should have said relay here but i had fuses on the brain) have a diode built in (typically 30amp up) as mentioned by SKYBEE.

Something else worth considering is the way the relay is mounted. A 60amp relay has a (relatively) heavy set of contacts. If it isn't mounted upright they can stick easily due to gravity.

I've seen this problem with the factory relays located next to the ecu in the footwell as they were mounted upside down. Turned them 90 degrees and the problem went away.

Edited by BHDave
Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1726273
Share on other sites

relays are sprung so any way they go doesnt matter when not in use tehy wont fall down unless spring has sprung its last spring :D cheaper relays cheaper springs cant beat the bosch 150 relay so many uses so versitile even has a lug so you can screw it down

thast my experianc

Link to comment
https://www.sau.com.au/forums/topic/95019-relays/#findComment-1736214
Share on other sites

  • 4 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
    • But first....while I was there, I also swapped across the centre console box for the other style where the AV inputs don't intrude into the (very limited !) space.  Part# was 96926-4GA0A, 284H3-4GA0B, 284H3-4GA0A. (I've already swapped the top 12v socket for a USB bulkhead in this pic, it fit the hole without modification:) Comparison of the 2: Basically to do the console you need to remove the DS and PS side console trim (they slide up and back, held in by clips only) Then remove the back half of the console top trim with the cupholders, pops up, all clips again but be careful at the front as it is pretty flimsy. Then slide the shifter boot down, remove the spring clip, loose it forever somewhere in the car the pull the shift knob off. Remove the tiny plastic piece on DS near "P" and use something thin and long (most screwdrivers won't fit) to push down the interlock and put the shifter down in D for space. There is one screw at the front, then the shifter surround and ashtray lift up. There are 3 or 4 plugs underneath and it is off. Next is the rear cover of the centre console; you need to open the console lid, pop off the trim covering the lid hinge and undo the 2rd screw from the driver's side (the rest all need to come out later so you can do them all now and remove the lid) Then the rear cover unclips (6 clips), start at the top with a trim tool pulling backwards. Once it is off there are 2 screws facing rearwards to remove (need a short phillips for these) and you are done with the rear of the console. There are 4 plugs at the A/V box to unclip Then there are 2 screws at the front of the console, and 2 clips (pull up and back) and the console will come out.
×
×
  • Create New...