Shield & Sensor Ground Joint Connector

[Sector]

Can this connector be deleted? It's called ground joint connector (B83 on 2002 WRX wiring diagram) but according to the diagram, none of the pins are actually connected to the ground. They are just bunch of sensor wires ganged together. Are those trully grounds or just some sort of test points? Would sensors still work if I cut that connector out? Thanks.

[aquillen]

(edit: for your wiring, you must keep them all connected together - and to the ECM, but you could remove the connector and just wire/splice them if you want). The ground comes from the ECM to the sensors - on these wires.

About this grounding from the ECM in general - to understand the scheme...

Inside the block are different groups of wires tied to each other to make up specific ground or common circuit groups. So they not all one common ground bunch.

For example B83 - 1, 2, 3 = together, 5, 6, 7, 8 = together... (but read on - this is from Legacy/Outback - don't go by "mine"). In my drawings the W... connections go to the other drawing pages which are circuit groups. So these ground "groups" scatter around to things.

The ECM "sends out" grounds specific to each group (and/or) the grounds come in from other wires. Inside the ECM this is necessary to get the "best" grounding connections for the specific sensors. If the designer did not do this we would have sensors reading slightly off or worse, subject to electrical noise pickup problems leading to misbehavior, likely engine codes, misfiring, etc. You never know.

They can be deleted as a connector block to get rid of that bulk. See further down in these posts. For the 3.0 motor's Legacy based wiring plans (which I now know are more complex than the Impreza) you'd want to measure or study the factory wiring carefully to determine which ones tie together and then splice your cut out wires so you still maintain those connections. You can go three ways to do this: (1) from each end, pry out the back side plugs on B83 and examine the plugs carefully, possibly measuring with an ohmeter to work out which wires are tied together by the plug "guts". (2) Ohm out the wires going to the B83 and work out which ones are tied together (you must do this with all the ECM plugs, other connectors also disconnected or the ECM internals, sensors, etc., will fool your readings. (3) pour through the wiring diagrams until you go blind getting the B83 connections, until you find each one and trace them anywhere they are drawn until you know what is what (ouch). I've done all three.

--- Otherwise you cut them and you'll have sensors not working or worse.

Now the above is based on my project for Legacy/Outback 2002 wiring. This drawing shows the majority of the B83 in my wiring and gives you an idea of what to expect if you track down each wire for Impreza. I have not determined if some of the disconnections are real or just how I traced out the wires - so you can't just go by my print as it is now.

[Sector]

According to wrx wiring all connection are just tied together.

rps20170123_103638.jpg

[aquillen]

According to wrx wiring all connection are just tied together.

rps20170123_103638.jpg

You are correct. Blows my comment that Impreza will be similar to Legacy/Outback to smithereens. The B83 on your print has them all in one - so yes you could splice the wires together and drop B83.

I should have looked at the 02 Impreza drawing I have - sure enough much simpler sensor grounding. "LUCKY"

To better answer your question then, for your version of wiring, the ECM provides the "ground" at B19 out to the sensors. They all need to connect to that pin or you'll be missing several functions...

I revised my first post a bit to not mislead some other reader maybe.

[Sector]

2002 WRX. The reason I ask the question is that I've purchased my harness from another member who claimed the harness was modified to be plug and play but I didn't get to verify this due to having a different fuel pump setup. He did mention that there were few codes related to emission system so I've purchased code eliminator board and was in the process of installing it when I noticed that B83 was missing and all wires going to it were just cut at the base connectors. So hence my question if I should unwrap almost entirely harness and reconnect them back to each other as shown in the diagram?

[aquillen]

You do need to connect them up... I don't know about the sensor eliminator, so hope you have instructions with it, but if any of these are going to still be used they must have conn:

From 2002 Impreza service manual

B83-1(L) - ECM gnd to: [page 9-Q] - Coolant sens E8-1(BG) & Throt pos sens E13-2(BG) & Press sens E21-2(BG) & TGV angle LH E50-2(BG) & TGV angle RH E54-2(BG)

B83-2(LR) - ECM gnd to: Rear O2 B19-4(LR)

B83-3(GR) - ECM gnd to: Mass air flow sens B3-5(GR)

B83-4(GY) - ECM gnd to: [page 1-G] - Fuel tank pres sens R47-2(RG) (they don't often change color codes but it happens)

B83-5(Lg) - ECM gnd to: EG temp sens B279-2(Lg)

B83-6(LW) - ECM gnd to: [page 1-D] - Fuel temp sens R58-5(BY)

B83-7 x

B83-8(RG) - gnd from ECM: B135-19(RG)

[Sector]

Thank you for the input. Odd that person who sold me the harness claimed that there were only 3 error codes related to emmision system and all other sensors functioned correctly.

[aquillen]

Somewhere the working sensors have been connected to grounds, just not at this B83. It may work fine, but not as Suby engineers designed. It may not be an issue but if something odd happens in the future, related to a sensor that uses this ground, one fix may be to connect it as designed.

[Bob_n_Cincy]

Sector,
The engine harness does not need very much work. Just seal wires like the power steering and air conditioners clutch wires.
In my harness, whenever I had a splice point with 3 or more wires, I installed a ring lug and used a stud block post to splice them.
See picture below.
Bob

panel.jpg

[Sector]

Very neat. My harness is also only meant to run the engine. It looks like you are not even using fuel pump controller or even a relay. How are you hooking up the fuel pump?

[Bob_n_Cincy]

Very neat. My harness is also only meant to run the engine. It looks like you are not even using fuel pump controller or even a relay. How are you hooking up the fuel pump?

The one bundle on the far left goes to the front of the car. (my gas tank is in front)
That bundle includes wires for my:
1.Drive by wire pedal
2.fuel temp sensor
3. instrument cluster
4. OBDII connector
5. fan control
6. fuel pump control
7. ECU power

In the front I used the fuse box that is normally under the hood as my power distribution.
I made a conventional lighting circuit as opposed to the silly one Subaru had.
My steering column has nothing electrical on it.
Bob

[Sector]

Thank you for the info.