View Full Version : OBD2 plug, Roadster
Ok, thinking this may be a daft idea but then again, that's where the best ones lurk.
There is an OBD2 port on my Roadster, it still works with the 1zz ECU and i can pull and clear codes from it just fine. It throws up about 15 of them straight away though, seeing as there is no engine!
I'm obviously running the 1MZ ECU along side this.
From what i can see, to wire up an OBD2 socket it simply requires grounds, a live feed and one signal wire.
What i'm thinking, would it be possible to connect this 1MZ wire to the Roadster's original OBD2 plug?
I assume it will be coming out at the 1zz ECU, so simply cut that wire there and connect to the 1MZ OBD2 signal wire?
That way the standard plug has all the grounds and live pins sorted and is receiving signals from the 1MZ ECU. That correct or is there something i'm missing here?
Cheers,
Can't help you there matey, but got that plug for you here. Took ages to arrive, but will get it sent off tomorrow for you chap :thumbsup:
Whit? I thought it was one you had lying around from the old loom, didnae mean for you to go out and get one!
Cheers anywho's.
Ah it's cool, I bought a load of multi pin plugs so i can easily and quickly remove the looms from the car, the same place did OBD2 plugs pretty cheap too.
Ahh, above and beyond anyways chief.
Going to organise that Crail run very soon btw!
GregLeBon
16-09-2010, 22:05
Thats what Paul did on mine, Ollie: I've got live streaming of data, etc, using the JP701 MaxiScan reader........
Funky hand held number that, nice.
Got PCMSCAN here for the crap top and EMS327 connector, it's the dyno stuff i'm most interested in.
/big kid mode off
It's looking like W/G pin 11 top plug for the signal wire to the OBD2. 1MZ will be the SIL wire i imagine, will try it 2moro afternoon.
Depends on the protocol used but yes essentially its a 3 or 4 wire jobbie.... lee where did u get your plugs from? I've been looking for some decent auto loom plugs for ageesssss!
Paul Woods
17-09-2010, 07:30
Olie we wire the Roadster OBD2 plug up to the 1mz on all our swaps, connect the SIL line up and you're done, make sure you get it on the correct wire though or the protocol will be mixed up.
That's what i'm trying to figure out, is the 1MZ SIL going to the 1zz SDL or TC? Roadster plug has the 2 signal wires.
Depends on the protocol used but yes essentially its a 3 or 4 wire jobbie.... lee where did u get your plugs from? I've been looking for some decent auto loom plugs for ageesssss!
Used these chaps: http://www.northern-connectors.co.uk/product_souriau-851-mildtl26482-series-1-circular-connectors_153
We used them on Nimrod aircraft electrical stuff and never had a moments bother with the plugs, just everything else :icon_razz:
Think i've got it sussed.
Pin 5 on the 2nd top ECU plug (1zz) P/B was the TC also feeding a signal to the OBD2 plug. The 1MZ and 1zz protocols are different due to this extra input.
So i've removed that input and now simply have the grounds, the battery power and the signal from the 1MZ 8D White connected to the G/W signal wire for the OBD2 plug.
So i should have the OBD2 plug set up for the correct protocol on a 1MZ. It works with my hand held scanner but haven't tried the craptop and the EMS yet, will try tonight.
1zz fe appears to be ISO 9141-2.
Uses pin 5 Ground, 7 data, 15 data and 16 Power.
1MZFE appears to be SAE J1850 VPW.
Uses pin 2 data, 5 ground and 16 power.
So if we put the 1MZ SIL wire to pin 7 or 15, then the protocol will be incorrect for the 1MZ ECU.
We have to re-pin the obd2 plug to get the 1MZ SIL signal to pin 2. Pin 5 and 16 will be correct and pin 15 we simply remove the signal.
Just now, the setup i have, with the 1MZ SIL wire going to either pin 7 (G/W?) or 15 (P/B?). Surely that cannot work?
Unless the scanner can use the ISO 9141-2 protocol to read the 1MZ ECU?
Paul Woods
17-09-2010, 17:48
Olie you are making that far too over complicated mate, there is only one wire to join, forget the other earths and live wire, they are all taken care of, just join the 1mz SIL wire into the 1zz data terminal, job done.
The G/W wire?
That gives the wrong protocol for the 1MZ then shirley?
Then we'll have pin 5 ground, pin 7 the 1MZ SIL data, and pin 16 power. That's the ISO 9141-2 protocol (pin 15 is just optional). So the scanner reads the 1MZ with that protocol instead of the J1850 it's supposed to?
Paul Woods
17-09-2010, 18:31
I don't have my diagrams to hand to identify the correct 1zz data pin, but it doesn't matter what protocol you use, that is not tied to the ECU type, it just means the reader will pick up the order of the pins wether you use the 1zz SIL pin or 1mz SIL pin on the OBD2 socket, in short as long as the data stream is on one of the "protocols" the reader knows then it will recognize it. There is no such thing as the correct protocol for a 1mz, wire it up to any protocol you like, the reader will do the rest, it doesn't know it's a 1mz if you think about it, so supplying the data on the 1zz pin is fine.
Duff info, it seems they both use OBD2 protocol ISO9141-2.
Cheers Paul.
No idea why the scanner won't pick up the 1MZ ECU through the OBD2 port. Hrrmph.
Paul Woods
17-09-2010, 19:23
As i said before mate, you aren't on the 1zz data line, join the 1mz SIL line to it and it will work.
I've got it on the correct line White Pin 8 1MZ ECU D plug onto the G/W top plug on the 1zz "body side".
Handheld scanner reads fine on the right protocol but can't get it to work with the crap top.
You mentioned before you had a way of checking the timing on the 1MZ's, what are you using for that, a laptop program or is it a function of your handheld scanner?
Paul Woods
17-09-2010, 20:30
It's a function of my scanner, which is EOBD2 compatible, most scanners are only OBD2 or maybe JOBD2 compliant, mine does the lot.
You need an EOBD2 scanner to pull all of the data from a 1mz.
Have you forgotten all you learned here young jedi?
I mind you saying but never seen the scanner.
There must be some downloadable software that lets me use the laptop somewhere!
/Tight Scot mode off
I've got the same model scanner on from Pauls if you need to borrow it Olie?
Really is a good bit of kit :thumbsup:
snowtigger
17-09-2010, 20:57
He's still a padwan mate he hasn't reached Jedi hood yet oh master woods.
I've got the same model scanner on from Pauls if you need to borrow it Olie?
Really is a good bit of kit :thumbsup:
Aye, i'll swing by some point next week if you're about chief, nice juan.
Powered by vBulletin® Version 4.2.5 Copyright © 2024 vBulletin Solutions Inc. All rights reserved.