Minimum wire harness for engine operation?

[CrankyOldMan]

tl;dr - I'm hoping that someone here has experience with setting up a 1NZ in a minimal install state, or at least getting one to fire up when removed from the vehicle.

I'm planning to do a 1NZ-FE swap in my MK1 MR2 (http://www.yarisworld.com/forums/showthread.php?t=55525) in the near future, and I'm gathering intel on the electronics side. It's my first engine swap, so there's a lot of undiscovered country here for me.

I've got the EWD for the 1st gen Scions and I'm comparing it to the Echo wire harnesses that I've seen on ebay. The ECU has 4 plugs: 2 go into the engine bay, 2 go into the interior. It looks like the main engine wire harness will cover all of the basic connections (battery, ground, injectors, coils, etc.) and since I won't be using any of the interior stuff (A/C, radio, window motors) I don't see a need for the two interior connections. Of course, that all depends on what wires are actually in those other two connectors. I'm laying out as much of the EWD as I can in a separate schematic to verify all the connections, but it's a huge spaghetti mess, complicated by the 2006.5 change and the AT vs MT differences.

The plan is to use the existing instrument cluster since all of the indicators are standalone gauges, but add the OBD-II port for diagnostics and possibly monitoring other systems. There's a guy that's already done a 1NZ-FXE swap into a MK1--and can do the wire harness for $400--but I would like to do the work myself and save the cash. There's also the option of building a MegaSquirt ECU and doing away with the OEM ECU altogether, potentially in concert with forced induction. I've got a salvaged Blitz S/C kit and a brand new Ogura TX-07 compressor that can be pieced together to that end.

I've also go access to pin crimp and removal tools for many popular types of automotive connectors at work (Sumitomo being one of the biggest pains in the ass) so I could in theory do it without spliced/soldered connections.

So what say you, YW? Do we have the collective knowledge and experience to pull this off?

EDIT: added link to pinout

2000 Echo ECU pinout (https://docs.google.com/spreadsheets/d/1P81L9-DD-QsGgZkyWTiLX3iDYy5T8wBYDlkIiZ9r7xU/edit?usp=sharing)

[CTScott]

I have been helping a gentleman with putting a 1NZ in an old Morris Mini and using an early Echo ECM and engine harness is definitely the way to go. With it you will also want the Echo cable throttle. The minimum to run is really what plugs into the long block (injectors, coils, cam sensor, crank sensor, and MAF, Throttle position, and power to the fuel pump). To run well you will also need coolant temp sensor, O2 sensors, knock sensor, and the OCV.

If you eliminate all of the emissions stuff (pump, canister, etc.) you will always have a CEL.

[CrankyOldMan]

Ok, that's pretty much what I was thinking, but it's always good to have someone confirm it. The cable throttle is a must, since the MR2 is cable as well. I'm debating if I want a bigger throttle body to go with the S/C--mostly because of the limited options in OEM upgrades and lack of IAC on an aftermarket universal unit.

From this 2001 Echo listing on ebay (http://www.ebay.com/itm/2001-Toyota-Echo-Engine-Wiring-Harness-1-5L-wire-harness-OEM-T0261-/271890102415?hash=item3f4de9b88f:g:Y~YAAOSwl8NVb2v D&vxp=mtr) it looks like the main wire harness uses three of the ECU connectors, but one of the two other white connectors nearby may be related. I'll spend some time over the next few days putting a ratsnest together in EagleCAD to see what ends up going where.

[CTScott]

Ok, that's pretty much what I was thinking, but it's always good to have someone confirm it. The cable throttle is a must, since the MR2 is cable as well. I'm debating if I want a bigger throttle body to go with the S/C--mostly because of the limited options in OEM upgrades and lack of IAC on an aftermarket universal unit.

From this 2001 Echo listing on ebay (http://www.ebay.com/itm/2001-Toyota-Echo-Engine-Wiring-Harness-1-5L-wire-harness-OEM-T0261-/271890102415?hash=item3f4de9b88f:g:Y~YAAOSwl8NVb2v D&vxp=mtr) it looks like the main wire harness uses three of the ECU connectors, but one of the two other white connectors nearby may be related. I'll spend some time over the next few days putting a ratsnest together in EagleCAD to see what ends up going where.


There are 4 connectors which go to ECM on the Echo.

[fnkngrv]

Can't wait to see how this pans out for you

[CrankyOldMan]

Can't wait to see how this pans out for you
It won't be anything terribly exciting at first, just comparable to stock engine performance. After that, though, sky's the limit!
There are 4 connectors which go to ECM on the Echo.
Correct. The photos of the main engine wire harness clearly show three connectors on the interior side of the main grommet (E5-E7 if I'm not mistaken) that are grouped to go into the ECU, but there's a separate tendril between the ECU and the grommet with two more white high-density connectors that I can't clearly differentiate from the diagrams in the EWD. The newer Toyota EWDs use color-coded images for each separate wire harness, but this old one is just B&W, so the actual routing gets lost in the image compression.

[fnkngrv]

How did you source the 1nz?

Sent from my XT1575 using Tapatalk

[CrankyOldMan]

How did you source the 1nz?

I haven't yet. There's a few different sources locally that have them in the sub-$500 range. Higher mileage, but I would probably rebuild it anyway.

[CrankyOldMan]

Went to the local u-pick yard today and pulled an '00 Echo A/T ECU and wire harness. I can confirm that one of the ECU connectors comes from the dash/interior wire looms (E4) and the other three are from the engine bay. The two other white high-density connectors on that end are IE1 and IE2 (wire to wire connectors). There's three Echos at the other location, hopefully one will be an MT. There were a few Yarii as well, but I don't want to screw around with immobilizers and all that for this project.

[Bluevitz-rs]

careful, some of the earlier years use a different computer and wiring that later years. Just make sure everything mates up.

I worked on someone's '02 and it had a different wiring layout than my '05

[CrankyOldMan]

careful, some of the earlier years use a different computer and wiring that later years. Just make sure everything mates up.

I worked on someone's '02 and it had a different wiring layout than my '05

Definitely. I've got the EWD for all 6 years of the Echo and all 3 years of the xA and xB. The harness I got today had some internal cuts and a missing connector, so I'll need to either rebuild this one or try and get another one from the other yard.

[CrankyOldMan]

Out of curiosity, I wandered on to the MegaSquirt products page and found that they sell a PNP kit for the Echo (http://www.diyautotune.com/catalog/diypnp-nippon-denso-76pin-unassembled-kit-p-384.html) (lots of other vehicles fit, too). So even if this harness is a bust for the current application, I can use it as a base for a standalone setup.

[CrankyOldMan]

Just a quick update on ECU connectors.

E7 (26 pin) is required, as it connects the injectors, ignition coils, crankshaft and camshaft position sensors, and oil control valve (VVT-I). It also connects the idle air control valve and VSV (EVAP) coil.

E6 (16 pin) is required, as it connects the MAF sensor, throttle position sensor, knock sensor, and primary oxygen sensor. It also connects the engine temperature sensor (may be needed for warmup/idle) and some unneeded things: max hot/foot mode sw, power steering pressure sensor, vapor canister pressure sensor, and a few others that I can't track down at the moment. The secondary O2 sensor is connected via one of the internal wire-wire connector blocks, but it may be optional as well.

E5 (12 pin) is only required if the ECU requires speedometer input, or if you have an automatic transmission (ewww!).

E4 (22 pin) seems to be optional for everything except the combination meter, unless the BATT signal on pin 1 is something other than battery voltage sense.

Also got some info on the diagnostics, since it's NOT CAN-based OBD-II. It's M-OBD on pin 7 (SIL) and uses a different protocol--possibly covered elsewhere in the forums.

[CTScott]

Just a quick update on ECU connectors.

E7 (26 pin) is required, as it connects the injectors, ignition coils, crankshaft and camshaft position sensors, and oil control valve (VVT-I). It also connects the idle air control valve and VSV (EVAP) coil.

E6 (16 pin) is required, as it connects the MAF sensor, throttle position sensor, knock sensor, and primary oxygen sensor. It also connects the engine temperature sensor (may be needed for warmup/idle) and some unneeded things: max hot/foot mode sw, power steering pressure sensor, vapor canister pressure sensor, and a few others that I can't track down at the moment. The secondary O2 sensor is connected via one of the internal wire-wire connector blocks, but it may be optional as well.

E5 (12 pin) is only required if the ECU requires speedometer input, or if you have an automatic transmission (ewww!).

E4 (22 pin) seems to be optional for everything except the combination meter, unless the BATT signal on pin 1 is something other than battery voltage sense.

Also got some info on the diagnostics, since it's NOT CAN-based OBD-II. It's M-OBD on pin 7 (SIL) and uses a different protocol--possibly covered elsewhere in the forums.

M-OBD is a Japan-only thing. The Echos did predate CAN, but were standard ISO9141 for OBD.

[CrankyOldMan]

M-OBD is a Japan-only thing. The Echos did predate CAN, but were standard ISO9141 for OBD.

So pin 7 is functionally a K-line OBD-I signal?

[CTScott]

So pin 7 is functionally a K-line OBD-I signal?

Yes - K line for OBDII (OBDII became the standard in 1996).

The 2nd Gen Yaris actually still uses it for some systems, including the SRS.

[CrankyOldMan]

Yes - K line for OBDII (OBDII became the standard in 1996).

The 2nd Gen Yaris actually still uses it for some systems, including the SRS.

So then it's a single ended signal? I found a basic description as it being 10k4 baud with 0-12V logic, using UART timing. Any chance there's a document describing Toyota's implementation/protocol?

[CTScott]

So then it's a single ended signal? I found a basic description as it being 10k4 baud with 0-12V logic, using UART timing. Any chance there's a document describing Toyota's implementation/protocol?

Toyota has some custom PIDs, but it is fully ISO9141-2 compliant for HW and SW protocol. When it first came out and code readers were $1000+, I got my hands on the ISO docs and built a code reader with one of the SW engineers that was working for me at the time. We intended to bring it to market as a low cost reader, but since we were working on it on the side, by the time we fully completed the project $100 Chinese readers hit the market.

[CrankyOldMan]

Yeah, the engineering world is surprisingly cutthroat when it comes to knockoffs.

I spent a bit more time today going over the wire harness. Took off all the A/T stuff that isn't needed, made a few pin swaps to get some M/T wiring in the right spot, and started cleaning up my wiring schematic. Looks like the harness I bought is missing the TPS--bastards just chopped it right off instead of removing it. There are still about 10 wires on the E4 connector, since I don't know for sure what signals the ECU requires to operate. I'm going to put together a spreadsheet with the pinouts of each ECU connector to help with collaboration.

I also scored a '14 Yaris A/T ECU and engine wire harness today as well, with the intention of making a piggyback wire harness adapter from it.

[fnkngrv]

Looks like the harness I bought is missing the TPS--bastards just chopped it right off instead of removing it.


Same pinout as our current gen TPS?

Also what are you going to do about the throttle body and IM?




Sent from m-o-b-i-l-e

[CrankyOldMan]

Same pinout as our current gen TPS?

Also what are you going to do about the throttle body and IM?

No, it's the previous gen with separate TPS and IAC valve.

I'm not 100% sure what the plan is for IM. Somewhere between all OEM bits, a 1ZZ (cable) TB, and the Blitz S/C. I had also debated using the Yaris manifold and adapting a universal TB, but that means no IAC--which may be a pain in the ass.

[fnkngrv]

Ah ok. That is a bummer.

Sent from m-o-b-i-l-e

[Bluevitz-rs]

'02 Corolla Used a cable throttle if your looking for a bolt on upgrade.

[CrankyOldMan]

'02 Corolla Used a cable throttle if your looking for a bolt on upgrade.

I looked at that on some Scion forums. Needs a block off plate for the difference in IAC channel locations, but seems to be a decent option.

[CrankyOldMan]

I added a link to a spreadsheet in the original post with the ECU pinout and wire colors. If you would like to add to it, PM me the info, or I can add you as an editor.

[madgarage]

Where have you found the exact pinout for the ECU?
Im looking for 3 days now and i can't find it.
I have swaped the engine and the wiring loom.
my first ECU was a Bosch 0 261 208 036 89661-0D210
and the second is a fujitsu 89661-52065

And even if have changed the whole engine harness there is one connector which is different, it was connected from ecu to the blue plug, but in the new ecu the blue plug is missing

[CrankyOldMan]

I purchase a subscription to techinfo.toyota.com. Looks like you're in the UK? You should probably use https://www.toyota-tech.eu/ to make sure you get the right manuals.