Check your cam and crank sensors. See if you are getting voltage to their pins at the ECU when cranking.
no power to fuel pump!!!!
- Thread starter mk3tattoos
- Start date
mkiiichip;1689030 said:
My apologies, wasn't aware it was a Jz swapped car as I rarely read sigs...
The FP terminal on the diag box bypasses all relays and is directly connected to the fuel pump. If B+ to FP does not operate the pump then your wiring to the pump is bad or your ECU B+ bus is not getting any power when the IGN switch is on. Diagnose each separately.
As soon as the wife gets back I will check that out, watching the kids right now.
I was thinking it might be my mines ecu, but wouldn't I still get power to my safc if the ecu crapper out on me?
I was thinking it might be my mines ecu, but wouldn't I still get power to my safc if the ecu crapper out on me?
IJ.;1689060 said:
No worries, nothing a "180 thread flip" cant fix.
3p141592654;1689102 said:
This should be true, but since this is a swap, that is only true if the diag block was wired in the same way it was designed.
mk3tattoos;1689107 said:
One more time, the 1jz ecu does not signal the fuel pump relay. It is other wires involved in the swap. Many install a togle swich to ground the fuel pump relay, Dr tweak sells a RPM activated relay with his setups. Like I said its all in how you wired it.
I understand that the ecu does not send the fuel pump signal.
Let's say my ecu took a shit on me, wouldn't I still get power to my saf since it just tapped into the wires that power the ecu?
I'm sure the wiring on the 12v mod is good, it's been running for 6months now and I had a 12v mod on my 87 for 3 years.
My diagnostic box is wired up, I have been able to run the fuel pump by jumping b+ to fp before.
I'm working on checking stuff now.
Let's say my ecu took a shit on me, wouldn't I still get power to my saf since it just tapped into the wires that power the ecu?
I'm sure the wiring on the 12v mod is good, it's been running for 6months now and I had a 12v mod on my 87 for 3 years.
My diagnostic box is wired up, I have been able to run the fuel pump by jumping b+ to fp before.
I'm working on checking stuff now.
So it's 1am and I am stumped. Although I have tracked down a problem to the fuse box by the battery. I am only able to get 0.37v from the redwire with black stripe, it is the +B switched power that goes to the ecu and that is the same wire the safc is powered by.
I pulled the fuse box apart and looked underneath to make sure the +B was plugged in good.
I did not test the cps yet, I wanted to find out why I was not getting power to the b+ wire first.
Pinouts that I did test for volts were
13-IGSW- ignition switch am2- 11.98v
12-+B-switched power- 0.37 v
2-batt-battery-0.04v
1-BT-switched power-0.37v
Also ckecked the conectivity on B+wire and it was good.
Ckecked all fusible links in fuse box, seemed good and also switched the main relay out with one from my 87, did not help.
I pulled the fuse box apart and looked underneath to make sure the +B was plugged in good.
I did not test the cps yet, I wanted to find out why I was not getting power to the b+ wire first.
Pinouts that I did test for volts were
13-IGSW- ignition switch am2- 11.98v
12-+B-switched power- 0.37 v
2-batt-battery-0.04v
1-BT-switched power-0.37v
Also ckecked the conectivity on B+wire and it was good.
Ckecked all fusible links in fuse box, seemed good and also switched the main relay out with one from my 87, did not help.
Not really sure on the swap wiring or anything about your ecu. But the one thing I am looking at is your batt input to it comes directly from the "efi 15amp fuse" in the fuse box next to the battery, I would check that one first. And I wouldnt just look at it, actually check resistance to make sure there is a short between the two spades. After that possibly a problem with your efi main relay, same fuse box next to the battery, but this wouldn't be causing 0.04 volts on the batt input to the ecu unless the relay shorted out somehow and is puting that 15 amp efi fuse to straight to ground but that should blow the fuse regardless. Good luck with it, hopefully this helps some.
If you have only 0.04V on your BATT terminal at the ECU then you have found your issue. That should be 12V all the time.
I am thinking it is somthing with the fuse box itself, like a broken conection or something. I tried the mail relay from my 87 but it is a difrent relay than the one that is in the 1j, the numbers are diffrent. So I'm thinking it would not work with it.
Were can I get a main relay for the 1j, or are they all the same?
Were can I get a main relay for the 1j, or are they all the same?
Did you check the efi fuse yet? The power that runs through the contacts of the efi main relay come directly from the efi fuse then run directly through the circuit opening relay to the fuel pump relay. The batt+ that goes to your ecu is in parallel with the main efi relay, meaning directly after the efi fuse in between the fuse and your main relay is where the batt+ wire is ran. I am not disagreeing about it possibly being a connection in the fuse box though, it might be, but my first check would be that fuse.
Last edited:
Sounds to me like the wiring with the swap. With my x90 I had to make all the connections for the mreal, batt,and b+1. over by the battery and fuse box is your MA70 c1 plug. this delivers all the signals to the ECU.
.
This is where the JZA mates up with the Ma70 body harness. I would check all those wires for Continuity.
Here is the order the are in
1 Batt signal from 15A EFI fuse Black and yellow
2 M-Rel coil signal from ECU Black and Orange
3 Plus from Haz Horn fuse (15A) for Theft deterrent horn Not in use
4 Plus from EFI main relay (via 15A EFI) Black and red
5 GND signal for Air flow meter switch (GE engine?) Not in use
6 A/C water temp switch Not in use
This is where the JZA mates up with the Ma70 body harness. I would check all those wires for Continuity.
Here is the order the are in
1 Batt signal from 15A EFI fuse Black and yellow
2 M-Rel coil signal from ECU Black and Orange
3 Plus from Haz Horn fuse (15A) for Theft deterrent horn Not in use
4 Plus from EFI main relay (via 15A EFI) Black and red
5 GND signal for Air flow meter switch (GE engine?) Not in use
6 A/C water temp switch Not in use
Agreed. The problem is not a relay, so forget about it. Focus on getting 12V to your BATT circuit. Fuse is a good start, as is the connector mentioned above.
Thanks for the good info matt! I have been tattooing non stop since Monday so I have not had to check anything out
but tonight I plan on working on it all night!
Can mods move this thread the 1j section......did not think it was going to be a swap issue.
but tonight I plan on working on it all night!Can mods move this thread the 1j section......did not think it was going to be a swap issue.
i put in a new fuse box but it did not work. so were the main relay goes i used a wire with a 15fuse and plugged it in to two points that would go to the power wire and it worked. i had to leav for work but when i get back i will dig in further, but i think it is the main relay.
shoud the 7mgte main relay work in place of the 1j relay?
shoud the 7mgte main relay work in place of the 1j relay?