PCM wiring issue
 

So, soldered in replacement PCM connectors, rechecked everthing, and had my electrician neighbor put eyes on the connections as well, checking for color mismatches.

went to start it to day and I have a P2128

and a U2023

also, the ebcs is chattering like when Nish sent me a test map for it

there are a few same color wires that could have been crossed, particularly on plug A

rechecked the ebcs, it is correct, at least the 2AA pin shows continuity to the EBCS harness terminal

while checking the accelerator pedal wires, I noted an odd thing.

Pin 1AJ shows on the PCM pinout document as a green/black

on my new, and checked, old, plug its green/red, and is soldered to a green/red wire in the harness

and there is no green/red showing on the schematic for the A plug, and I did the 2 plugs separately

also, the plug to the accelerator itself, has 2 green/yellow wires


grrrrrr

Thoughts??

@ALPINEST4RS;

Ohm check from end to end. That code is for a voltage issue for the APP.

right on, trying to find the right size probe to mimic a PCM pin want to avoid stabbing my nicely heatshrunk joints


do you know where the "drive by wire" relay is located ?

I was crude on Plug "A" and just cut all the wires, finding out latr that there are 6 blacks, 3 black/yellow, etc
lottsa fun playing inspector cloueso with a multimeter

on B/Y is driv by wire, and one of the 2 whites is acc ped pos

pretty sure the B/Y are good, cuz the clutch switch works, and I got a chirp while pinning the AC relay, "which is Identified"

how bout the "drive by wire" relay

would like to confirm the green/yellow on pin 1BF is correct as well. since there are 2 green/yellow wires on the acc ped connector @ALPINEST4RS;

need the year, ill check my wiring diagrams.

07 GT

and I just confirmd 10 sec ago that
1AQ, and 1AC are crossed.

fixing now


And THANK you

I forget my manners at times
@ALPINEST4RS;

I may be good
regarding ACC harness


the black is good
the green/ blk-red? is good
the white was crossed with the cruise circuit white : fixed
the rest don't share color

the 2 green/blue, the injector relay one pinned correct

the black/yellow, 2 of the 3 known good, so.........

I'm inclined to put power to it again

Thanks!

@ALPINEST4RS;

Sigh,

fixed above, tided up, reset codes

cranks, no fire
P0089
P0098



and the U2023

waiting on a ride to work tommorow, and any thoughts from you kind folk

done for the day..
@ALPINEST4RS;

check your connections again man. something isn't right.

Data log of the last cranking. this threw the P0098, and P0089

And i have pinned and confirmed continuity on quite a few terminals relating to FP and air temp to include all 4 MAP harness leads

got some black/reds that aren't showing continuity yet, namely the egr/ and flapper valves, track that down today

Need that ah ha moment
@ALPINEST4RS; @Code Monkey;

You don't need those to run a car, can just leave them disconnected, at least for the time being?

Oh, absolutely, but if the b/r for the flapper doesn't pin continuity to terminal 2AM, where is it going? and what is going to 2AM that should be going somewhere important etc, etc, etc


on plug A, i really effed up and cut the whole plug off, then when I weeent to solder leads, I realized there are several wire of the same color on that plug:bukkake:

Kinda wishing I'd just replaced the entire harness at this point, or, not tried to clean it in the first place, even better

I'll give it another day or 2 of detective work

Ah it's not a big deal man, you just need to triple check everything. FYI the pin out diagrams are the back side of the connector where the wires pin.

Some auto companies do male/female side.

Yeah, They ID that in the manual Ex, C_B_A, witha little glif showing a arrow of viewpoint

The hopscotching colors when the main harness breaks to the "injector" harness is kinda sucky

Well Guys,
Where I am at now is with a short to ground on terminal A of the MAF, and cam sensor, and term C of the crank sensor.

all these shorts clear when the connector with the blue lock handle is removed from the under hood fuse box

anyone look underneath the fuse/relaytray??
the terminals for the main relay are not acting quite right either. none of them are grounded, and 2 have continuity to Bat

To check for proper short to ground. Both ends of the harness need to be disconnected. If you unplug that connector both ends, then test to ground you should have OL "nothing" if there is any type of ohm reading its shorted. Only end to end should should have a reading, typically .2-.3 ohms.

I got your pictures, I'm still lost man. Best bet is to start over when all these problems happened. When the new connector got put on.

My electrician neighbor loaned me his tone generator, I'll play with that for a bit.

I just bought a civic so I can have something reliable.

This short, a few weeks after the whole PCM swap fiasco has taken the wind out of my sails.

Fuckin Car

@meicalnissyen what was the original issue? I just love ecu issues.... haha. Isn't that right @ALPINEST4RS?!

From the original picture looks pretty fugly.

I'm in Singapore for another week, but I have an entire 07 GT spare harness available for chopping up if you need specific plugs and pigtails. Just have to wait till I get back for proper signage and such lol

Harness is for everything in the engine bay.

Much love brother

I paid used retail for a harness, wishing I'd gone to the trouble to install it as is

I did a nice job of splicing the PCM plugs onto my harness, all correct, but a ghost short has manifested

If I fail to find it, I may take you up on your virgin replacement

tag a couple LBFM's for a fellow vet

Not a virgin replacement. Long story short, I had a wire short (fuel injector common for injector 1 and 3) and it actually slightly melted my ECU connector. That through my ECU for a loop, this is how the car would act although EVERYTHING read ok (outside of the crazy lean AFRs). Swapped ECUs and it's all good.

Before I swapped the ECU, I swapped out every part imaginable with regards to the car running lean; including the harness. I had the pleasure of having locals installing things, so I just had a donor car available for things like the TB and O2 sensors.

That being said, I would not let you use this as a plug and play harness since it fried my ecu... However, the sensor and pigtails for the rest of the engine would be fine, I could just chop off whatever it is you (may) need.

As for ground, the one on the HPFP is a very common one to cause very sporadic issues. Have you checked all major grounds? Off top of my head.. I can think of a few: PMM, HPFP, one under the HPFP by whatever sensor that is and the one by the driver side of the hood.

Of course there are others, but I can't recall more right now.

Thinking on a tangent, if you crank but no fire, what is your HPFP pressure at with the car off and after attempting to crank? Maybe the relieve valve is stuck open or shut. When mine was stuck shut, I could crank and not fire; HPFP pressure was 2k+psi and slowly bleeding with the car off. Of course this was after the car ran (and died from not being able to open the relieve valve). because of that, I now own a 32mm box wrench haha.

Super longshot.. but how's the MAF sensor look?

Issue (unrelated to yours, but the reason I won't let someone use my harness):

https://www.youtube.com/watch?v=uZSDFTt5yg8

Last cranking log I took showed HPFP at 1650+, and boost at 32psi, codes as above
PCM was not part of the issue (see thread)
the 3 known affected circuits are CKP, CMP, and MAF all grounding the reference voltage terminal.

Of note, not grounding to pop a fuse, melt a wire etc, the short goes thru a 33 ohm resistance.

If that's a clue to anyone, Chime in please !!

After cranking, what what the HPFP pressure while the car sat idle?

Good Q

in a normal situation, how long could pressure be held in the rail above ITFP?

Cuz that engine hasn't been over 250 rpm in over a month

The MAP sensor harness checks out correct on each pin, yet reports a pegged boost value
The CKP harness has a short to ground on term A, but reports engine RPM as 200 ish cranking

I'll check the spill valve next time I get the motivation to look at the car, but there is more going on...

Check the cranking log in post #9