Looking at the waveform if A is +ve supply to IMV and B is the PWM control then you are loosing the 12v to the IMV the moment current flows. Your average of 800ma seems way too low.
If you measure V on that line with a DVM it will tell you B+ no problem, but put a 2A test light on it and it will not light and the voltage will disappear.
I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run. The ECU is shutting it down when it realises that it can not control the fuel pressure.
Also the ECU is trying to control the IMV, I added a maths channel for the -ve duty of the IMV control and you can see the ECU puts it up to almost 100% as the FRP rises- not sure about the wiggle in the middle - probably ECU attempting to unstick a solenoid, or it might just be from the low battery
I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run. The ECU is shutting it down when it realises that it can not control the fuel pressure.
Also the ECU is trying to control the IMV, I added a maths channel for the -ve duty of the IMV control and you can see the ECU puts it up to almost 100% as the FRP rises-
Thank you, i looked again at the PWM of the IMV and indeed it appears the ECU is trying to control it.
It is fixed now
High resistance in power supply to ECU, It has 4 B+ supplies, just one had failed.
I suspect if you check the wiring diagram you should be able to give a (fused!) 12v to that line and expect to see the car run.
I tried that and it would not run, exactly the same !! that is possibly made me look at ECU power supply
Last edited by Iver on Thu Sep 29, 2022 6:24 pm, edited 3 times in total.