Thread: Reading and Interpreting FSM help please

I am trouble shooting and unsure about what to test with my volt meter.
The manual shows to disconnect the relay from the connector.
I get that , - (ground) goes to ground.
Do I test 2 and 5 terminals independently or do I connect 2 and 5 together to + (red)?

Anyway this is on page EC-1609 of the 03 Sentra FSM


My hope is that if I can trouble shoot through this P1122, I will eventually get better and do an engine swap. Baby steps.

might have better luck if thread wasnt labelled 00-01

Originally Posted by Scrapin

might have better luck if thread wasnt labelled 00-01

Thanks, I agree, There is a problem with the forum, when you post a new thread and select "QR25DE" for prefix it gives you 00-01 right now unfortunatley.

oh ok, well that will be fixed shortly, thanks for bringing it to out attention.

Yes, no problem, I just wish I could figure out my wiring problem. Oh well I'm buying a house right now so my time is limited anyway.

Originally Posted by 5er

I am trouble shooting and unsure about what to test with my volt meter.
The manual shows to disconnect the relay from the connector.
I get that , - (ground) goes to ground.
Do I test 2 and 5 terminals independently or do I connect 2 and 5 together to + (red)?

Anyway this is on page EC-1609 of the 03 Sentra FSM


My hope is that if I can trouble shoot through this P1122, I will eventually get better and do an engine swap. Baby steps.

check them one at a time, 2 and ground, 5 and ground
did you do a throttle relearn?

Big thanks tunedslick for the advice. Yes I did a throttle relearn, didn't get me outa limp mode. I tested like that the other day and one of those is problematic. I have to test again tomorrow morning and continue. I'll update then.

The good news.... after trouble shooting 1122 the code disappeared.

The bad news.... codes 2135, 0222, 0223, 0122, 0123 all popped up, all TPS Throttle Position Sensor codes..

I'm really good at testing voltages and continuity, and pedal dance key turning learning now, since I tested everything as described in the FSM for these codes.

Everything checked out as good sort of...



My reading for 73(TPS1) Fully released .76V
My reading for 73(TPS1) Fully depressed .96V

My reading for 74(TPS2) Fully released 4.36V
My reading for 74(TPS2) Fully depressed 4.18V


When I say sort of I mean the variance on my readings is only .20V and .18V

This is with a new rebuilt TPS (Throttle Body and sensor from Rock Auto).

Anyway I'm still in Limp mode, throwing the same codes.

I think it's the ECU at this point, what do you guys think?

By the way no air leaks past MAF, new PCV Valve, thats all!

Well, I think I'm going to re-install my old TPS and see if the readings are the same. If they are then I have to assume it is my ecu creating my trouble and replace it.

^-- good idea...im curious as well

No one else got input? Where's the brains at?

You know what is annoying?! When you order a 5L ECU and you get a 5P after waiting a week for shipping. I'm pissed right now. I guess I'm driv'in limp to my new house on Wednesday. Fuck.

whats the diff in the ecu's?? the immobilizer?? if it is theres a way to bypass it...

My car has no NATS immobilizer system, my new ECU is a NATS ECU. So I think I would have to buy the rest of the NATS system to make the NATS ecu work, and do some re-wiring. I've read that there is a way to change from Nats to non-nats, but if there's a way to by-pass it on the ECU only I'm super interested. Does this make any sense?

ohhh i see what youre saing... damn im stumped.

Originally Posted by 5er

My car has no NATS immobilizer system, my new ECU is a NATS ECU. So I think I would have to buy the rest of the NATS system to make the NATS ecu work, and do some re-wiring. I've read that there is a way to change from Nats to non-nats, but if there's a way to by-pass it on the ECU only I'm super interested. Does this make any sense?

there is a way to jump it from inside the ecu but its more complicated then the how to i did and if you're not electronically inclined i don't recommend it

oh, if you're gonna convert your car to NATS you'll need the NATS module, minor wiring and someone to program your key/ecu/immobilizer

Originally Posted by tunedslick

there is a way to jump it from inside the ecu but its more complicated then the how to i did and if you're not electronically inclined i don't recommend it

Hey if I screw up the ecu by jumping it from the inside, no big loss. However if I jump it and it works it would be like winning the lotto. I'm not afraid to try.... hey I took grade eight electronics and made a photo electric night light... LOL Oh and it worked Anyway I'd rather not pay nissan to program keys and buy Nats stuff at this point. I'm trying to keep my costs on tha down low cause I just blew the biggest wad ever on my house and I gunna be paying for that shit a loooonnnggggggg time

well its simple reversed, instead of the harness you're doing the pins inside the ecm

It would be nice if we could make Nats ECMs into non-Nats ECMs

Replacement 5L in my hand right now :damnit1: