Wireing woes

[Paulpen]

Basically after decluttering the whole car loom for the RB25 onevia (RHD UK spec S13) im in a tad of a pickle with a few circuits

These being the fuel pump and heater

Ive done quite a bit of work on the fuel pump issue so here goes.

The pump is good as 12v across it makes it work.
The pump to engine bay wiring is good.
The fuel pump relay works when teted but wont when in normal setup.
In normal setup the relay has 12v at 3 pins but not the one to the pump.
2 of those wires are black/white and are therefore 12v so are correct.
The other wire is black with a pink trace that goes from the fuse box through connector F10 to the ECU. Am I right in thinking this should be a switched ground and not 12v ?


As for the heater issue here goes.
The fan works fine on all different speeds however I can get the recuirc flap or any of the different vent direction flaps to move. Also the lights above the vent positions do not light up.

Anyone had this issue before and would it be something to do with me removing all of the air con wiring ?

[lazysk8er2]

I have the same problem with my center panel. i cant change the flaps from defog or feet to face etc. also none of them light up either. i bought the car that way im gonna look into it tomorrow

[Paulpen]

I have the same problem with my center panel. i cant change the flaps from defog or feet to face etc. also none of them light up either. i bought the car that way im gonna look into it tomorrow


Exactly the same as mine then - does your recirc button work at all ?

[Z U L8R]

i just did a mode door actuator for a custome's s14 this week because it was stuck blowing only in defrost position.

obviously before i deduced and isolated the problem to the actuator i checked out the fsm via alldata and made sure everything was getting power/ground like it should and the signals changed as you changed what you wanted as far as defrost, feet, face, however the actuator did not move all the way. it moved like 5 cm then bound up. i took it off (4 phillips screws) and just verified that there was no blockage hindering the flaps from moving freely, therefore deducing the problem to the mode door actuator (which is right by your gas pedal with a brown plug on the side of the center console under the dash. there's also another one above that that's for the fresh air or recirc. and then you have your blend door which either directs air to blow over your evaporator (ac) or your heater core (head) when selected via the control head.

if your control head doesn't light up at all....then first check that it's getting power, then check that the actuators are getting power, and if all looks kosher then you may have to start with a known good control head.

as far as the fuel pump, you are correct the two black/white are ignition power, the ecu gives the black/pink ground, then the relay clicks over and sends power to the black/yellow which ends up going to the fuel pump. i've seen many sr ecu's with the fuel pump circuit fried. it's not uncommon.

the only REAL fix is to get another ecu....

however an easy fix would be for you to cut the black/pink at the fuel pump relay and ground it to the chassis on the relay side since the end that goes to the ecu side is doing nothing you can tape the end and let is lay there for later when you get a power fc or other means of replacing the ecu.

this will give your relay the ground it needs to click over to send power to your fuel pump, however your fuel pump will run whenever the key is in the ON position whether you've started the motor or not.

really the only difference between doing it like that and the factory way it's set up is instead of priming your fuel pump for 10-15 seconds when the key is on (factory)

it'll prime your fuel pump as long as the key is on lol

the ecu will keep a ground on that black/pink as long as it sees the motor is spinning via the cam angle sensor, therefore if you roll your car over and the motor stalls out then your fuel pump will shut off (factory)

versus, as long as the key is ON your fuel pump is on.

that's the only differences. your car will still run and drive the same. not really a big deal for the time being, just don't flip your car over and catch on fire and you'll be fine :D

Dave

[g6civcx]

Does the fuel system have the pressure control solenoid? The US never got that. Does yours?

[lazysk8er2]

Exactly the same as mine then - does your recirc button work at all ?

nope nothing but the fan speed works...i bought my car half assed to begin with.

[Paulpen]

Wll 8 hours today and now they both work - thankyou for the input guys it made alot of sense and got my head going the right way about it.

The fuel pump issue was easy when I stepped back and thought about it. All the car wires wier as they shuld be ad going to the right ECU pins os it was either ecu or not enough earths.
Seeing as there was no engine in there I though the pleanum earths didnt need to be connected but I was wrong - give them an earth and all tickedy boo :D


As for the heaters thats what took most of the time with the fsm and a few spare parts.

Tried swapping both the recirc motor and flap motor but still nothing. It had to be a wire issue but where to start.
All the flap wires went to the controler along with the recirc ones too, there was earth and live at the controller etc. All the fsm wireres were where they should be but one !
Turns out that there was a wire totally missing from the bottom right of the white controller plug (should be a blue/orange there with 12v). Im guessing it goes to the interior fuse box but I have no way of putting a plug in there so I teed it off the fan motor connector on the controller as its a nice thick wire thats next to it.
Dong the above gave me the flap motor and the lights on the buttons but still no recirc.
Much fiddling and head scratching and spare loom tracing led me to see there was a wire missing from the motor connector ( hould be 3 wires not 2). This missing wire also is 12v so now links into where the other one does to keep all the heater 12v's together. Still no worky though.
So I took the spare climate control cntroller I had apart and compared the circuit boards and they looked the same so this was the last shot and guess what - it works now :D. On closer inspection of the old circuit board it looks like its cooked in a few places.

All happy now so just need to work out where to put the engine bay fuse box now so I can get a front facing inlet in there :-/

[Z U L8R]

cool man, glad you figured it out. a couple of good pick tools and you can repin/depin nissan plugs pretty easily.

Dave =]

[Paulpen]

cool man, glad you figured it out. a couple of good pick tools and you can repin/depin nissan plugs pretty easily.

Dave =]

All I had a was a scrap loom and a paper clip :(

Any luck with yours lazysk8er2 ?

[lazysk8er2]

nope not yet i actually ran into a different problem which im currently diagnosing which is a no restart problem. but after that is settled i will post my findings.

oh how i hate wiring lol.

[Paulpen]

nope not yet i actually ran into a different problem which im currently diagnosing which is a no restart problem. but after that is settled i will post my findings.

oh how i hate wiring lol.


I know exactly how you feel - one thing down and another turns up :rant2: