Vaughan

All ECU power grounds should go to the same location on the engine, usually on RBs that's at the front of the intake manifold.

logs and scope won't show me anything, if you left the wire in then ECU still running after removing your ground pin will be because the ignition switch input would have been active pulling that pin to ground. In terms of ground issues make sure that the ECU power grounds on the engine are securely bolted to an unpainted surface

A quick google shows that the JZX110 tacho signal might be on pin Q20 not Q26 (using pin numbering from Altezza pinout in help manual), have you swapped any pins around to make your JZX110 engine work? did you move the tacho wire to the appropriate place? Do you have the tacho output setup in the ECU? (Aux 3 in the Altezza)

Grounding Pin 16 will power the ECU and engine loom, if the ECU powers up and runs with pin 16 not connected to anything that would suggest a backfeed issue, can you confirm whether your pin 16 not being grounded test was with the pin removed from the header or the pin left in the header? Have you altered any of the factory wiring or added any extra wiring to the ECU like adding a boost solenoid etc?

If you get the serial data working you could hook it up to a digital input into the ECU or over CAN just as a yes/no for ECU Antitheft and you could also integrate it into the starter control. That is assuming arduino doing the talking over serial and then sending a yes/no to the ECU

Voltages don't seem low enough to turn the ECU off but it definitely sounds like you have an ECU grounding issue if the ECU earths are 1v higher than the chassis. Can you also see if the blue lights on the ECU PCB turn off when cranking? Also if that was done with coils and injectors unplugged then it may be even worse with those connected

Try again but leave the Mode set to Off instead of User Defined. And don't forget to click apply or Ok between each attempt, might even be worth storing and power cycling between each attempt.

The Imo pin has single wire serial communications on it and we found under our testing with a key start 86 and a push start BRZ that you don't need to do anything on that pin to have the immobiliser light not show up. In terms of utilising the factory immobiliser you would need to decode how that serial communication works. There is no antitheft signal setup in the Link CAN

Your tune shows OBD being off on both CAN buses, you need to go into the CAN Setup window, "Select ISO 15765 on CAN 2", select CAN 2 in the CAN module box, set the bit rate, click Ok, then press F4 to store the change to the ECU.

I've only used the Android app not the apple one sorry, your CAN Bus 2 is being used for the vehicle CAN bus so best course of action is probably to borrow an android phone if the apple version of the app doesn't support the 500kbit/s Link mode.

What devices are on your CAN bus and what bit rate are they each set to talk at? Everything on the bus must run at the same bit rate, the CAN gauge can be set to be 500kbit/s or 1mBit/s when selecting the mode in the mobile app for it, the Link CAN Lambda bit rate can be set in the CAN Devices tab of the CAN Setup window.

G4+ is a bit more awkward than G4X as G4X has CAN based PWM outputs. For G4+ I would say use the fuel pump function and send the fp dc over CAN to the PDU and then use a virtual aux with a gp output that controls which pump is being used so the PDU gets an effort % and a this pump or that pump message over CAN. In terms of determining a failing fuel pump you'll want to have it latch onto the backup pump on failure of the primary which can be done by feeding a gp output's own state back into itself and you might also want to look into detecting a failing pump by watching how much current it draws through the PDU. If you have a manifold pressure referenced fuel reg then you'll want to look at differential fuel pressure not fuel pressure for your failing pressure. As a side note do the pumps need to be PWM'd?

I am around yes

cranking, coils and injectors can most likely be unplugged. you are trying to see why the ECU disconnects when you crank and so you need to see if there is a massive voltage drop on cranking that would turn the ECU off.

Pin 49 is the ECU power, pin 45 is just part of a circuit that turns on the ECCS relay so start with pin 49 power with your ground probe on one of the ECU power grounds.

If the ECU disconnects while cranking then start checking what happens to the voltages to the ECU while cranking. For the gtr plugin the ignition switch signal comes in on pin 45 which when powered grounds pin 16 which triggers the ECCS relay which supplies power to the ECU through pin 49. The ECU Power grounds are on pins 10, 20, 107, 108 & 116.

can you attach a PCLog of an attempted start and a Trigger scope taken while cranking please.

Your stoich, Fuel density and other fuel related settings are using pure gasoline values, stoich for 10% ethanol for example would be 14.13. Have you confirmed the flow rate, deadtime and spwa values for the injectors that you are using with the fuel that you are using on Link hardware? different fuels. like ethanol, have different flow rates in the same injectors. If you do get your injectors tested for flow rate, deadtime and spwa be sure to use a G4X or G5 Link ECU as the hardware controlling the injector in that test as the driver chip used affects the deadtime. The K20 sample map was based on a Japanese model DC5 Type R and so I wouldn't be shocked if your injectors are different.

Based on your earlier basemap I would remove the filtering from trigger 1&2 and set your trigger 2 arming threshold value to 0.3V. Note in that trigger scope the trigger setup is happy and synced, are you seeing spark being triggered now?

If your ECU disconnects when you start cranking you have wiring/power issues you need to sort, start by confirming that the ECU is connected prior to start of cranking and then disconnects during cranking, if so start checking what the battery voltage is doing at the battery and at the ECU noting that the ECU uses an ign sw input to control the ECCS relay which supplies power to the ECU.

That help manual stuff you are quoting is from the G4X/G5 help manual For High pressure Direct injection pumps. I would assume in your particular case you are wanting to do two low pressure fuel pumps for Port injection. If you are wanting to talk to a PDU over CAN then depending on the PDU you could just have the ECU send regular single pump control and then have the PDU do the swap over, what PDU are you using? Are you wanting to regularly swap which pump you are using or just always one and then the other only if the first fails? are you allowed any crossover time if you are changing between pumps occasionally?

yes, runtimes are only updated by the ECU, not by PCLink

CLL uses the Lambda Target value which is affected by what is in the Lambda overlay and so the Lambda overlay table will affect what CLL does.

The LS Standalone ECU is on of our wire-ins which is physically different hardware to the plug-ins, we can change plug-in bottom boards but not the entire ECU.

All devices on the bus need to run at the same bus rate, leave it at 500kbit/s and when setting up the CAN gauge in the mobile app use the 500kBit/s version of the Link mode instead of the standard Link mode.