Fuel Pump FC connection and COR
#1
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From: exo-reality -wave if you see me; Front Range, CO
Fuel Pump FC connection and COR
Hi.
In the process of checking my wiring and as many circuits as I can think of, I also was checking my fuel pump (back in APril. Went sailing for few weeks and been back at it now for couple of weeks.
1999 3.4 MT into a 95 4runner.
in '20 while still working I did wiring on my week off inbetween rotations. Typically would think I got it (write down the important parts), come back couple of weeks later and do it again. Then compare, with reference to dntsdad and the Monch's write ups mostly. Then did my actual harnesses probably few months later by that time.
So here is my issue. I started by checking my TopSecret Kill Switch (basically just interrupts the pwr to the pump, after all the COR goodness). Fail. double check all that before I get the carpet and seats back in. Pwr direct to 'downhill' side of switch works fine. So I made a test light and put in place where my switch is, but still nada. So over the past cpl weeks been looking/searching for swap threads to see what others have done.
And continue to test. So after all the trials and testing (did find 35 ohms in my clutch safety switch. So at this point I have basically just jumpered around it so 'clutch is permanently depressed'. Reading Monch's thread and jumping around my COR relay I was pretty sure I failed to connect the COR pin 4 (on original 3vz wire harness) to the FC pin E14-3 (IIRC) on the 99 ecu.
If you've stuck with me so far, this is the crux. Checked all three sheets I had, and even wrote "DONE" on the pinout sheet. But as I'm always a DA, finally decided yesterday to pull evap and blower unit out, split my loom back open and follow the G/Y wire. It seemed good. Ended up bustin open my IH-1 connector, plugged in dummy bypasses and try again. Nada. Check with the ol meter. Sho nuff, I do have 12V (actually 10 some cuz battery is week unless I put charger on it.). However there is ZERO continutiy to ground on pin 3. Even pulled plug out of ECM, cut/made a pin from the old 94's ECU pin to fit INTO the E14 plug. Have continuity all the way back to EFI relay. So try again, and when I use my little bypass and touch to the frame - bingo. My test bulb monstrosity comes on.
Q: This (the connection of the FC signal - which is actually just 12V from the Switched Power side of EFI relay) activates COR closing pins 1 and 2 (pwr for physical pump). If I supply ground rather than dependind on the ECM to ground that circuit, it works. Can anyone think what I might be missing? I prayed for two days that I was just a dumba and forgot the g/y. I'm beginning to fear my ECM will not (for whatever reason) pull that pin to gound.
I did NOT connect the MREL (on the 99 that just provides coil power for the EFI relay). Didn't think its needed. I aslo need to double check (haven't got to it yet) the STA circuit. Think I'll redo dash harness wire and move the 'clutch safety' stuff 'upstream' of the Start Relay, so Start relay coil power goes to STA (e14-7). In fact I may not have that correct either. Altho the 99 EWD description refers to it as a Source in one location, and an input signal (in the Starter Circuit section) otherwise. Seems good way to roast some TTL crap.
Can't believe I'm having all this trouble, because litterally no one else ever seemed to stuggle with this issue. But don't trust my thinking anymore either. Caught myself multiple times using Black as a groiund (vs White or some combo as Toyota typically does). Big Evil Red Oil Services company always did stuff different.
Any words of wisdom greatly appreciated.
In the process of checking my wiring and as many circuits as I can think of, I also was checking my fuel pump (back in APril. Went sailing for few weeks and been back at it now for couple of weeks.
1999 3.4 MT into a 95 4runner.
in '20 while still working I did wiring on my week off inbetween rotations. Typically would think I got it (write down the important parts), come back couple of weeks later and do it again. Then compare, with reference to dntsdad and the Monch's write ups mostly. Then did my actual harnesses probably few months later by that time.
So here is my issue. I started by checking my TopSecret Kill Switch (basically just interrupts the pwr to the pump, after all the COR goodness). Fail. double check all that before I get the carpet and seats back in. Pwr direct to 'downhill' side of switch works fine. So I made a test light and put in place where my switch is, but still nada. So over the past cpl weeks been looking/searching for swap threads to see what others have done.
And continue to test. So after all the trials and testing (did find 35 ohms in my clutch safety switch. So at this point I have basically just jumpered around it so 'clutch is permanently depressed'. Reading Monch's thread and jumping around my COR relay I was pretty sure I failed to connect the COR pin 4 (on original 3vz wire harness) to the FC pin E14-3 (IIRC) on the 99 ecu.
If you've stuck with me so far, this is the crux. Checked all three sheets I had, and even wrote "DONE" on the pinout sheet. But as I'm always a DA, finally decided yesterday to pull evap and blower unit out, split my loom back open and follow the G/Y wire. It seemed good. Ended up bustin open my IH-1 connector, plugged in dummy bypasses and try again. Nada. Check with the ol meter. Sho nuff, I do have 12V (actually 10 some cuz battery is week unless I put charger on it.). However there is ZERO continutiy to ground on pin 3. Even pulled plug out of ECM, cut/made a pin from the old 94's ECU pin to fit INTO the E14 plug. Have continuity all the way back to EFI relay. So try again, and when I use my little bypass and touch to the frame - bingo. My test bulb monstrosity comes on.
Q: This (the connection of the FC signal - which is actually just 12V from the Switched Power side of EFI relay) activates COR closing pins 1 and 2 (pwr for physical pump). If I supply ground rather than dependind on the ECM to ground that circuit, it works. Can anyone think what I might be missing? I prayed for two days that I was just a dumba and forgot the g/y. I'm beginning to fear my ECM will not (for whatever reason) pull that pin to gound.
I did NOT connect the MREL (on the 99 that just provides coil power for the EFI relay). Didn't think its needed. I aslo need to double check (haven't got to it yet) the STA circuit. Think I'll redo dash harness wire and move the 'clutch safety' stuff 'upstream' of the Start Relay, so Start relay coil power goes to STA (e14-7). In fact I may not have that correct either. Altho the 99 EWD description refers to it as a Source in one location, and an input signal (in the Starter Circuit section) otherwise. Seems good way to roast some TTL crap.
Can't believe I'm having all this trouble, because litterally no one else ever seemed to stuggle with this issue. But don't trust my thinking anymore either. Caught myself multiple times using Black as a groiund (vs White or some combo as Toyota typically does). Big Evil Red Oil Services company always did stuff different.
Any words of wisdom greatly appreciated.
#2
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Joined: Jan 2011
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From: exo-reality -wave if you see me; Front Range, CO
Oooff. If any home gamers are still looking for answers, my problem might be presence of Anti-theft system wiring.
Now trying to figure out IF the donor vehicle had it. And if so, how to plumb around.
Now trying to figure out IF the donor vehicle had it. And if so, how to plumb around.
#3
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From: exo-reality -wave if you see me; Front Range, CO
In case anyone is lurking and laughing.
Toyota tech today looked up my vin and "It was shipped with a transponder key".
Not sure what a Transponder looks like; on the 99 it appears to be close to center of the dash. And I sure did not get a key fob.
So IFF I can find it, probably best option would be to wire it back in, and then get a transponder key for that VIN. Thoughts?
Or anybody have a clue about the insides of the ECM for the black box? REading and it almost looks like theres a random code sent to the ECM along with some sort of verification that the key is legit, for internals to function.
For sure my wires are all correct. Took dash back apart, Rewired stuff, ;pulled E14 plug and checked Voltages on plug. Even have system V on the FC signal. So it is NOT going to ground. Would image theres also disable circuits on the ignition side too.
Toyota tech today looked up my vin and "It was shipped with a transponder key".
Not sure what a Transponder looks like; on the 99 it appears to be close to center of the dash. And I sure did not get a key fob.
So IFF I can find it, probably best option would be to wire it back in, and then get a transponder key for that VIN. Thoughts?
Or anybody have a clue about the insides of the ECM for the black box? REading and it almost looks like theres a random code sent to the ECM along with some sort of verification that the key is legit, for internals to function.
For sure my wires are all correct. Took dash back apart, Rewired stuff, ;pulled E14 plug and checked Voltages on plug. Even have system V on the FC signal. So it is NOT going to ground. Would image theres also disable circuits on the ignition side too.
#4
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Joined: Jan 2011
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From: exo-reality -wave if you see me; Front Range, CO
Immobilizer Programming
Posting this here so I can find it again.
Not sure why it posted the vid; but here is the reference v=-rtXpOWYx_U
Not sure why it posted the vid; but here is the reference v=-rtXpOWYx_U
Last edited by coopster; Jun 20, 2023 at 10:28 AM. Reason: post video number, not a real link
#5
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From: exo-reality -wave if you see me; Front Range, CO
Proper 3.4 ECU connections
An update. And to clarify if anyone comes across this.
I got hold of a SnapOn engine diags computer. It showed zero codes.
Took stuff back apart, tested all my connectors, etc.
Also, tried to make my harness as close as possible to 99 requirements.
In sum:
the MREL (signal out) to EFI relay is NOT needed.
Reconfigured my Clutch Start / Start / EFI stuff to get the 'downhill' side of Clutch switch into the STAT (a signal IN) pin.
The STAT is needed.
As so often I failed to yet document my changes, will do that soon and post. somewhere.
Bottom line, that was apparently my fail. Yesterday decided to "see what happens" and motor cranked. After maybe 5 rotations it fired right up.
Could hear some rubbing noise. Not sure what that was yet. But hit starter again, let run for 20-30 seconds to check oil pressure. Then shut off.
Pretty exciting. Small oil puddle, but hey. Got combustion.
I got hold of a SnapOn engine diags computer. It showed zero codes.
Took stuff back apart, tested all my connectors, etc.
Also, tried to make my harness as close as possible to 99 requirements.
In sum:
the MREL (signal out) to EFI relay is NOT needed.
Reconfigured my Clutch Start / Start / EFI stuff to get the 'downhill' side of Clutch switch into the STAT (a signal IN) pin.
The STAT is needed.
As so often I failed to yet document my changes, will do that soon and post. somewhere.
Bottom line, that was apparently my fail. Yesterday decided to "see what happens" and motor cranked. After maybe 5 rotations it fired right up.
Could hear some rubbing noise. Not sure what that was yet. But hit starter again, let run for 20-30 seconds to check oil pressure. Then shut off.
Pretty exciting. Small oil puddle, but hey. Got combustion.
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