Car no start.... please help
The PCM feeds 12VDC to the fuel pump relay, different than the fan relays where it switches ground instead.
You'll only see that 12VDC for ~2sec after you turn the key to <RUN> position with the engine not running.
So...either you're not testing that circuit correctly...waiting longer than the ~2sec to hook up your meter or whatnot...
Or...you have your wiring wrong and the PCM isn't seeing the key switch go to <RUN> position.
You'll only see that 12VDC for ~2sec after you turn the key to <RUN> position with the engine not running.
So...either you're not testing that circuit correctly...waiting longer than the ~2sec to hook up your meter or whatnot...
Or...you have your wiring wrong and the PCM isn't seeing the key switch go to <RUN> position.
Thread Starter
On The Tree
Joined: Jan 2007
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umm... the guy before you said you have to give the pink/black wire 12volts? i didn't do that. but then crainholio says you don't have to give it 12 volts. i have everything wired and grounded (relay) and the fuel pump isn't kicking on. anyone else have input?? thank you guys.
Originally Posted by natedawg
umm... the guy before you said you have to give the pink/black wire 12volts? i didn't do that. but then crainholio says you don't have to give it 12 volts. i have everything wired and grounded (relay) and the fuel pump isn't kicking on. anyone else have input?? thank you guys.
Let's start referencing the circuits according to their connector and pin to avoid any more confusion.
C101/E you need to feed ignition-switched 12VDC...so that, as I said, the PCM will see the key in the <RUN> position.
C101/D is 12VDC out from the PCM to the fuel pump relay, it has 12VDC supplied by the PCM for ~2sec when the ignition key is turned to the <RUN> position. That 12VDC pulls the relay, which closes the high-amperage fused 12VDC circuit to the fuel pump.
TECH Apprentice
Joined: Aug 2006
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From: Mobile AL.
just wire it up from my last post (which is nothing but the FAQ with alittle more input) and you will be fine. it aint hard. im sure i have the shitest wiring job of any of the 240 swaps and me and my wife (yes my wife uses it alot, more then me) have been driving mine for 9 months. no problems.
sounds like your only problem is no power on the pink/black.
sounds like your only problem is no power on the pink/black.
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Joined: Aug 2006
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From: Mobile AL.
Originally Posted by crainholio
The PCM feeds 12VDC to the fuel pump relay, different than the fan relays where it switches ground instead.
You'll only see that 12VDC for ~2sec after you turn the key to <RUN> position with the engine not running.
So...either you're not testing that circuit correctly...waiting longer than the ~2sec to hook up your meter or whatnot...
Or...you have your wiring wrong and the PCM isn't seeing the key switch go to <RUN> position.
You'll only see that 12VDC for ~2sec after you turn the key to <RUN> position with the engine not running.
So...either you're not testing that circuit correctly...waiting longer than the ~2sec to hook up your meter or whatnot...
Or...you have your wiring wrong and the PCM isn't seeing the key switch go to <RUN> position.
after those 2 sec the only thing that triggers it after that is the motor turning over. if there is any rpms on the motor the pcm triggers it.
Thread Starter
On The Tree
Joined: Jan 2007
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ahh i think i forgot to wire in c101/ E. I just did all the pink wires I'll have to check that in the morning. thanks guys.
Btw dude I thought you were talking about the 240sx's blk/pink wire in the f3 plug. that goes in to the 240 relay. not the ls1 pcm one. thanks though i got it now.
Btw dude I thought you were talking about the 240sx's blk/pink wire in the f3 plug. that goes in to the 240 relay. not the ls1 pcm one. thanks though i got it now.
Thread Starter
On The Tree
Joined: Jan 2007
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Originally Posted by fouz65
if you have the 3 plugs that come off the ls1 harness (which i hope you do).
C101 Plug
A YEL/BLK Low Coolant Sensor
B PNK Hot in Run and Start (IGN/INJ Bank 2 15A)
C BRN PCM 36 Air Pump Relay Control
D DK GRN/WHT PCM 9 Fuel Pump Relay Control
E PNK/BLK PCM 19 Ignition Positive Voltage for PCM
G ORN PCM 57 Battery Positive Voltage for PCM
H BLK/WHT Ground
K GRY/BLK PCM 53 TCS Spark Retard Signal to Brake Control Module
this pink/black wire your talking about not having power sounds like c101/e. you have to add power to it. it dont get it from everything else.
all in all
1 orange=hot/battery
1 black= ground
5 pinks(counting the one with black stripe. 2 pinks on c100, 2 pinks on c101 and 1 pink on c105)=ign. run to ign, turn key, they get power.
1 green/white on c101/d=fuel pump. or run the fuel pump to battery to make sure it runs, for testing.
1 purple=start position on key. or just tap it to the battery till it starts and take it off as soon as it starts so you know your motor runs.
you need nothing else to hear it run. 1 hot, 1 grnd, 5 ign, 1 starter and ofcourse that flamable stuff.
C101 Plug
A YEL/BLK Low Coolant Sensor
B PNK Hot in Run and Start (IGN/INJ Bank 2 15A)
C BRN PCM 36 Air Pump Relay Control
D DK GRN/WHT PCM 9 Fuel Pump Relay Control
E PNK/BLK PCM 19 Ignition Positive Voltage for PCM
G ORN PCM 57 Battery Positive Voltage for PCM
H BLK/WHT Ground
K GRY/BLK PCM 53 TCS Spark Retard Signal to Brake Control Module
this pink/black wire your talking about not having power sounds like c101/e. you have to add power to it. it dont get it from everything else.
all in all
1 orange=hot/battery
1 black= ground
5 pinks(counting the one with black stripe. 2 pinks on c100, 2 pinks on c101 and 1 pink on c105)=ign. run to ign, turn key, they get power.
1 green/white on c101/d=fuel pump. or run the fuel pump to battery to make sure it runs, for testing.
1 purple=start position on key. or just tap it to the battery till it starts and take it off as soon as it starts so you know your motor runs.
you need nothing else to hear it run. 1 hot, 1 grnd, 5 ign, 1 starter and ofcourse that flamable stuff.
okay i went out and test the relay right this morning and it didn't come on. then i took my harness all apart and started looking for C101/e and couldn't find it. i could only find 3 and they just ran from the pcm to the engine. i clipped the end off of the one plug i need to find. you said it goes to pcm 19? red or blue? Blue is just pink ignition positive voltage (pin 19) and red has no pin 19. i'm rather confused. my engine is a 2000 and i read pin outs and only pink/black wires is.
-Blue pin 3 injector 3 control
-Blue pin 61 camshaft position sensor reference low.
-the last one i'm not sure of it's not on my pin out list but it was connected at both ends.
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Verdad Gallardo TECH Apprentice
Joined: Aug 2006
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From: Mobile AL.
i did nothing to the pcm red and blue plugs. everything you need is on the there plugs that come ff the harness, if you have them. if you dont then your harness is cut or you/someone changed it. i never change nothing in the stock harness.
quick question. do you have the there plugs coming off the harness?
quick question. do you have the there plugs coming off the harness?
Thread Starter
On The Tree
Joined: Jan 2007
Posts: 125
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i did. i cut the end off the plug that had the pink/black wire in it. i put the ones i needed to where they need to go then taped off the wires i didn't need and ripped it all apart and searched all the wires i could only find 3 wires. shouldn't one of the wires go back to the pcm though?
check this out dood...mite be of some help...my 2000 ls1/t56 harness was slightly different on some pinouts...
http://www.dxsoftware.com/magnus/wiring.htm
http://www.dxsoftware.com/magnus/wiring.htm
Thread Starter
On The Tree
Joined: Jan 2007
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i noticed the relay was different... so i switched all the Nissan plugs around so it's the way you said it should be. then i tested voltage. at the ignition input it's 11.9volts. At the ls1 relay switch wire it was 10.7 and stayed that way the whole time even after the 2 seconds. Then while cranking on it... it kept jumping around from 2.5 , 5, 7.5 volts. any ideas?? is there a ground on the pcm for the fuel pump or does the blue vats fuel input wire matter? I don't think I hooked that up.
Thread Starter
On The Tree
Joined: Jan 2007
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ahh finally figured it out. i had to extend my tach and fuel relay wires. and i used the same red wire. just mixed them around... so now that works. that was a headache. but I'm having a problem building fuel pressure i have a walbro 255. it seems it has pressure before regulator. but the return (if i have the right line) and the line to fuel rails doesn't have much pressure. Is the return the same size as the input fuel line or is it bigger i believe the other line is 5/16's i also used the same old s14 sock so that might be a problem my new s14 walbro install kit wont be here for a few days i have 3/4's of a tank so that shouldn't be an issue.
