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Discussion Starter #1 (Edited)
UPDATE: problem solved, scroll down to read the solution. i have sent an email to rick to update his wiring diagram as it is incorrect.

background info: 2jz with 1jz electronics. have emu and wideband wired in at the moment

tps reads ~5.45v closed, and like ~5.9v wot.

i've checked wiring from ecu to tps, everything checks out. i have 5v at pin1, pin2 has 0v, and pin 3/4 have ~12v (all tested with key at ON position and tps disconnected).

once i connect the tps, pin2 reads ~5.45v, so i figured since all the wires go to the right pins, there must be a resistor that's burnt out inside the tps, so i went and got a brand new one from toyota.......same fucking shit. i have triple checked the wiring from the ecu plugs to the tps plug, it looks good, so where is this 5v coming from???

thanks

also, if it matters, i am throwing a sub-tps code (traction control), but i don't have it plugged in, and it doesn't matter if i plug it in. i don't know if they're connected, but thought i'd mention it
 

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Discussion Starter #2
update: i created a jumper harness strictly for the tps. i unplugged the 4 pins at the ecu going to the tps, and used some spare wires i had from another harness and ran it 8 inches from the ecu to the tps i had in my hand........same fucking results, so it's not my harness.

i'm going to try my ecu and tps on eric's car, we'll see how it goes.
 

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Discussion Starter #3
bullshit! it's proving to my damn wiring harness again.........such bullshit. i'll look into it further tomorrow
 

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Discussion Starter #6 (Edited)
well, i went and started unplugging every single wire going to the ecu and the body plugs, and the sensors trying to see which one would cause the voltage to drop.

unplugging the 5v feed for the tps (pin VC) at the ecu causes the voltage to drop to around 1v (which sounded good at first), but then when i go wot, it goes down to 0.7v

unplugging M-REL caused a no volt reading, with no change to tps output voltage when i depress the throttle

unplugging IGSW caused the same as above, but i assume that's cause the ecu doesn't know the key is in the ON position.

unplugging the 'X' ecu connector (the one with ignition signals and isc signals), and i get 12v's coming from the tps???

unplugging the 'U' ecu connector (one for cam/crank signals) doesn't nothing

did a comparison test of readings with tps, and without:

no tps/key on_______________tps/key on

pin6 (VTA2) 5v______________pin6 5v
pin7 (IDL2) 12v_____________pin7 5.52v
pin10 (VTA1) 0.86v__________pin10 5.45v
pin11 (IDL) 12v_____________pin11 5.52v


please, wiring genius', speak up!
 

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well, question is, are one of the 2jz sensors that your 1jz is hooked up to the same type of sensor or is it causing probelms.
 

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Discussion Starter #8 (Edited)
doubt it, as i unplugged almost all the sensors..........isc, iat, map, o2

i'm gonna go unplug the temp sensor since it seems to have a shared ground with the tps in the 2jz wiring diagrams

edit: disconnect efi water temp sensor, and nothing
 

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Discussion Starter #9
well, i made some progress.

i have gotten the tps to display the correct voltage and crap, and it revs nicely now. the thing is, the way i got it to work was to run a wire from the 4th pin of the tps (which is supposed to go to IDL2 on the flying lead) to E2 on the ecu. the reason i did that was because i remember comparing erics harness to mine, and his didn't have 12v on pin4 of the tps plug, but mine did. so then i looked at the wiring diagrams of the 2jz and the 7m, and they all grounded the tps via E2, so i tried it, and it is "feeling" decent now. i have double checked, and it's the flying lead that is putting out 12v.

can anyone explain why, and how to fix?
 

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Discussion Starter #10 (Edited)
ok, more progress update.

did some testing on eric's harness, and it looks like his ecu puts out 12v to the IDL2 pin on the flying lead, BUT his harness is grounded somewhere on that wire in between the ecu and the tps plug. and i checked, and i have continuity with some grounds on the harness. so it looks like the efi wiring diagram for the 1jz is missing that.

but my question is, even if i do ground that wire, won't it create a short circuit when i take a ground and a 12v source and connect them? i don't want to blow my ecu :( ......or is it going to be like a circuit breaker switch dealy?

aiyah, what to do???
 

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di_rosa said:
ok, more progress update.

did some testing on eric's harness, and it looks like his ecu puts out 12v to the IDL2 pin on the flying lead, BUT his harness is grounded somewhere on that wire in between the ecu and the tps plug. and i checked, and i have continuity with some grounds on the harness. so it looks like the efi wiring diagram for the 1jz is missing that.

but my question is, even if i do ground that wire, won't it create a short circuit when i take a ground and a 12v source and connect them? i don't want to blow my ecu :( ......or is it going to be like a circuit breaker switch dealy?

aiyah, what to do???
Okay, I opened up my harness today to make sure that my Map sensor wiring was not screwed up and stuff.

The flying lead has a blue/black wire and a brown wire.
The map sensor has a Blue/black wire, a lg/black wire and the Brown wire.

I pulled the wires apart, and the brown wires from both connectors are joined together at a common ground - all browns.

Brown from ecu harness /map sensor/flying lead. ( I guess all grounded)

The Blue/black wire from the flying lead / and the blue/black map wire are both joined at two places in the harness.
First a bit closer to the ecu side and then closer towards the Map sensor side.

From the second joint, one end goes to the Map sensor connector and the other joint goes to the tps.

Checked the voltage, but i only got 3.6 V on tps side...with key on.How come you are getting 12 volts??

Hope this helps the question u had about grounding. I even checked the ecu wiring diagram and it shows excatly the way I described.
 

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Discussion Starter #13
the blue-black i know is joined as the map sensor and the tps share the 5v feed, hence why you're getting around 3.6v. the brown wire is the key! if you look at the wiring diagram, it shows the brown wire going straight from ecu to the tps, but you already said it is connected to the same ground as the map sensor, therefore the wiringn diagram is wrong.

with the flying lead disconnected, key on, what voltage do you get on the brown wire?

if you get around 12v, then fuck it, i'm gonna ground this wire, 12v or no 12v
 

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di_rosa said:
the blue-black i know is joined as the map sensor and the tps share the 5v feed, hence why you're getting around 3.6v. the brown wire is the key! if you look at the wiring diagram, it shows the brown wire going straight from ecu to the tps, but you already said it is connected to the same ground as the map sensor, therefore the wiringn diagram is wrong.

with the flying lead disconnected, key on, what voltage do you get on the brown wire?

if you get around 12v, then fuck it, i'm gonna ground this wire, 12v or no 12v
You mean on the tps : check for voltage between brown wire and the blue/blk wire with flying lead disconnected?

I can post that result in a few...
 

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Discussion Starter #15
no, at the ecu. disconnect the flying lead. measure the voltage coming FROM the computer (ecu side) at the flying lead (brown wire, pin 7) and confirm you have ~12v. then measure the flying lead going TO the tps (harness side) for a ground

thanks for your help :bigthumb:
 

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Discussion Starter #16
well, while waiting for suprastanger to verify his readings, i decided to ground the IDL2 pin on the harness, and leave it disconnected.....and wow, everything is working good, no more tps and sub-tps codes, revving like a champ........so yeah, what is the flying lead used for again? cause mine, while stopped, doesn't seem to change anything?

i'm still scared to plug it in and fry my ecu, so i'll wait for suprastanger to respond
 

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well, remember, not to splice the brown wire to the blue/blk. YOU will have a short.. lol.

Brown is going and joining to all the common ground. Blue/blk is joining the the map and tps connection.

I separated the blue/blk wire from each other ( tps and Map) but my car was hesitating when i tried to drive.
As soon as i spliced the map and Tps blue/blk together..car ran smooth, so i left it as it is.
I will check voltage for u today.
 

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Discussion Starter #19
bump?

suprastanger, you still there? the suspense is killing me, i can only hope the tps is the cause of my lack of power as i have sorted out most of the other little problems
 

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di_rosa said:
bump?

suprastanger, you still there? the suspense is killing me, i can only hope the tps is the cause of my lack of power as i have sorted out most of the other little problems

lol,
Sorry man. I didn't get a chnace to check that voltage, been getting home quite late.
What was that voltage you wanted me to check??
Was it at the ECU fly connector?
Check voltage coming out of the ecu side between the two fly connector wires??
jst verifying.
 
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