Hey, is there anyone really knowledgeable on the ECU’s for these trucks here? I’m having some issues with my 1990 B2600i (posted on this forum, making a new post here since this is just about ECU) where the Main Relay isn’t being grounded by the ECU. It should ground with ign. on and then when cranking again. (That is Pin 1G on ECU, L/B wire)
I’d like to know what signals/conditions the ECU needs to know when to ground this pin. I know the crank angle sensor is sending a signal, I checked it with a diode and it’s blinking.
As far as I understand it, I should have a “tach” signal on the white pigtail at coil, which I don’t.
I’m not that knowledgeable on electrical stuff so I’d appreciate some help here 😅
