MikePowers Posted January 11, 2021 Report Share Posted January 11, 2021 Hi all, Please be gentle, this is my first time setting up an ECU. My car is an SW20 MR2, when I got the PNP ECU the car had a gen3 3sgte engine. However that engine was bad so we swapped it for a gen4 3sgte. They are very similar engines however there are some notable differences. Gen3 only has 3 plugs at the ecu, which fit directly into the Link G4. Gen3 uses a distributer and single coil. The gen4 has 4 plugs at the ecu, so will need to make a small conversion harness here. Gen4 uses CoP ignition with triggers from crank and cam sensors for timing. Otherwise the wiring setup and sensor setup is almost identical. I have pinouts for both the gen3 and gen4 stock ecu, also the Link g4. most of the pins in the mini conversion loom are simply just moving a single wire to the correct pin for the Link from the gen4 loom. The ecu is tst205+ with rev 1.5 pcb. with the extended input wiring also. Link map sensor, all other sensors are Toyota. My questions are: How do I change the pin/wire setup to fire direct ignition for the CoP instead of a single coil? Which of the timing triggers will the ECU use? Can it use both crank and cam and is there an advantage to using both? Which pins on the Link would be used for these timing triggers? I realise this isn't an ideal setup but with the ECU already here I have to work with what I have. The plan is to get some new connectors, one end with a female ecu plug for the gen4 loom and the other 3 male gen3 plugs to wire into the Link. The task is slightly simpler as Power Steering, Air Con and ABS have been removed, saving needing those connections. Also boost is controlled via a boost controller and not the stock VSV. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 11, 2021 Report Share Posted January 11, 2021 Crank sensor goes to trigger 1, cam sensor goes to trigger 2. The coil signals go to IGN 1, 2, 3, 4. Quote Link to comment Share on other sites More sharing options...
ellisd1984 Posted January 11, 2021 Report Share Posted January 11, 2021 Could you not just de- pin the gen4 cables from their connectors and insert them into the gen 3 connectors? The chances are there'll be the same pins but you would need to confirm this Quote Link to comment Share on other sites More sharing options...
MikePowers Posted January 11, 2021 Author Report Share Posted January 11, 2021 thanks for the fast replies! Adamw. thank you, that's so simple. I had hoped it would work like that, cheers for confirming it. Ellisd1984. I could get some gen3 plugs and just repin it, can't take them off the old loom as they are in use in another project. should be easy enough to get hold of new plugs. Someone else told me there is already an off the shelf adapter mini loom which would be great too. thanks for the help. Quote Link to comment Share on other sites More sharing options...
ellisd1984 Posted January 11, 2021 Report Share Posted January 11, 2021 you can still get connectorshttps://uk.rs-online.com/web/p/automotive-connector-accessories/7122497/?cm_mmc=UK-PPC-DS3A-_-google-_-3_UK_EN_Automotive+Connector+Accessories_TE+Connectivity_Exact-_-TE+Connectivity+-+Automotive+Connector+Accessories+-+7122497+--_-174516+6&matchtype=e&kwd-359557570925&s_kwcid=AL!7457!3!441868252272!e!!g!!174516 6&gclid=CjwKCAiAi_D_BRApEiwASslbJ8_eOw0KEsc--LFlhz6Ii6nrGihStvTDgpn3kslQdF_kdjpqA7RgxBoCVeAQAvD_BwE&gclsrc=aw.ds after chasing countless wiring issue I'm not a fan of adaptor looms as it just add so many more points of potential failure. Quote Link to comment Share on other sites More sharing options...
INSW20 Posted January 25, 2021 Report Share Posted January 25, 2021 Just want to confirm before I make the wiring change, Aux7 on a 3SGTE V1 (TST185+) can be used to drive the tach through a tach adapter? I'm running a coil on plug setup on a gen2 using the factory tach. I'm not getting any usable output from pin 20 (IGN1) and my tach doesn't function currently. The direction I've received from the tach adapter supplier is to change to an available aux output for it to function properly. Quote Link to comment Share on other sites More sharing options...
koracing Posted January 25, 2021 Report Share Posted January 25, 2021 On 1/10/2021 at 11:32 PM, ellisd1984 said: Could you not just de- pin the gen4 cables from their connectors and insert them into the gen 3 connectors? The chances are there'll be the same pins but you would need to confirm this Nope completely different connector and pin set. 1 hour ago, INSW20 said: Just want to confirm before I make the wiring change, Aux7 on a 3SGTE V1 (TST185+) can be used to drive the tach through a tach adapter? I'm running a coil on plug setup on a gen2 using the factory tach. I'm not getting any usable output from pin 20 (IGN1) and my tach doesn't function currently. The direction I've received from the tach adapter supplier is to change to an available aux output for it to function properly. #threadjacking That's your fuel pump output. I would choose another output. Aux 3 is your factory hi/low boost control ouptut. Aux 4 is your factory hi/low fuel pump voltage relay - either of these I have used to drive a MSD 8920 tach adapter on COP setups to drive the gen2 tach. Quote Link to comment Share on other sites More sharing options...
INSW20 Posted January 25, 2021 Report Share Posted January 25, 2021 20 minutes ago, koracing said: #threadjacking That's your fuel pump output. I would choose another output. Aux 3 is your factory hi/low boost control ouptut. Aux 4 is your factory hi/low fuel pump voltage relay - either of these I have used to drive a MSD 8920 tach adapter on COP setups to drive the gen2 tach. Yeah, complete jack. I was searching for tacho output and somehow ended up here... So I'll confirm if there's not already wire in pin23, but I'm not using the OEM fuel pump wiring at all, so I chose Aux7 due to its proximity to the current IGT (IGN1) pin, since I'm using the COP expansion harness already. Without the factory FP wiring, any problem with Aux7 then? Thank you! Quote Link to comment Share on other sites More sharing options...
koracing Posted January 25, 2021 Report Share Posted January 25, 2021 On 1/10/2021 at 4:52 PM, MikePowers said: Hi all, Please be gentle, this is my first time setting up an ECU. My car is an SW20 MR2, when I got the PNP ECU the car had a gen3 3sgte engine. However that engine was bad so we swapped it for a gen4 3sgte. They are very similar engines however there are some notable differences. Gen3 only has 3 plugs at the ecu, which fit directly into the Link G4. Gen3 uses a distributer and single coil. The gen4 has 4 plugs at the ecu, so will need to make a small conversion harness here. Gen4 uses CoP ignition with triggers from crank and cam sensors for timing. Otherwise the wiring setup and sensor setup is almost identical. I have pinouts for both the gen3 and gen4 stock ecu, also the Link g4. most of the pins in the mini conversion loom are simply just moving a single wire to the correct pin for the Link from the gen4 loom. The ecu is tst205+ with rev 1.5 pcb. with the extended input wiring also. Link map sensor, all other sensors are Toyota. My questions are: How do I change the pin/wire setup to fire direct ignition for the CoP instead of a single coil? Which of the timing triggers will the ECU use? Can it use both crank and cam and is there an advantage to using both? Which pins on the Link would be used for these timing triggers? I realise this isn't an ideal setup but with the ECU already here I have to work with what I have. The plan is to get some new connectors, one end with a female ecu plug for the gen4 loom and the other 3 male gen3 plugs to wire into the Link. The task is slightly simpler as Power Steering, Air Con and ABS have been removed, saving needing those connections. Also boost is controlled via a boost controller and not the stock VSV. Is the car running or able to run on the gen4 ecu already? 4 minutes ago, INSW20 said: Yeah, complete jack. I was searching for tacho output and somehow ended up here... So I'll confirm if there's a wire in there for it, but I'm not using the OEM fuel pump wiring at all, so I chose Aux7 due to its proximity to the current IGT (IGN1) pin, since I'm using the COP expansion harness already. Without the factory FP wiring, any problem with Aux7 then? Thank you! According to the help menu the output for tach on Aux1-4 is 4000Hz max, and 5-8 300Hz max. I'm unsure if that would cause any type of limit on the 3SGTE as I've never scoped the tach signal, so I'm unsure if 300Hz max would be an issue. In my own designs/wiring I try to use 1-4 just so I don't run into that possible limitation. Theoretically you would have a max of 4 pulses per cycle and maybe 8000 rpm or 133 rotations per second. 4 * 133 is 533Hz. Again I'm not sure if that is the trigger pattern that comes out for the tach signal or not. Quote Link to comment Share on other sites More sharing options...
MikePowers Posted January 25, 2021 Author Report Share Posted January 25, 2021 Thanks for the replies people I did get plugs from RS, thanks for the tip. The car has been test started on the gen4 ecu, yes. We didn't run it for long as intakes, coolers etc are still being installed. With our lockdown it's hard to work on the car at the moment. The plan is to build this mini adapter loom so the stock ECU can still be used until we can get to the dyno for full mapping. Any issues and the stock ECU can go back on. A summer wire tuck project will then remove the gen4 loom and ECU, move the G4+ to the cabin and fully rewire the engine loom for that routing. This way the stock parts can be used for our other gen4 swap, or sold off. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 25, 2021 Report Share Posted January 25, 2021 3 hours ago, koracing said: 4 pulses per cycle and maybe 8000 rpm or 133 rotations per second. 4 * 133 is 533Hz. There are two crank revolutions in a 4 stroke cycle. Tacho output will be 267Hz @ 8000RPM for a standard 4cly tacho. So Aux 7 is fine. Its generally only 8cyl and above that you need to choose the tacho aux output with consideration of max frequency on G4+ and older ecu's. Quote Link to comment Share on other sites More sharing options...
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