Hoping someone on here can help me out. I just sold my dearly beloved 1991 DA9 after owning it for 4 years and pouring so much heart and soul into it. Well the guy who bought it from me somehow managed to brake the button on the clutch pedal that engages the interlock switch the very first day. After some troubleshooting and looking he finally saw the piece he broke off on the floor. Well I guess somehow while he was troubleshooting the main relay and fuses to see if that was the problem beforehand he did something and now with the new button the car will try to crank over but will not start. He noticed the fuel pump would not prime and after some more troubleshooting we noticed the ECU does not power on. We tested the car with another ECU to see if it was the ECU but the same thing. No power?!?!?! The CEL comes on the dash and stays lit but the LED on the ECU that is suppose to come on and go off does not when we look through the window. The main relay has been replaced and all the fuses are good. Is there any thing we’re missing?
are you positive the ecu fuse is good? don’t eyeball. use a multimeter. this will also tell you if you have power at the fuse
Oh believe me we checked every fuse we can possibly see. We’ve been using one of those fuse checkers that probes the backside pins of each fuse.
I’d say actually take the fuses out. I’ve read someone was having electrical problems, checked all the fuses with the pin thing your talking about, and they all checked out fine. But when he took it out it was just a little cracked and still making a connection, I geusse every bump would short it, then come back
have you checked to make sure the ground on the t-stat housing is connected? also make sure it has a good ground, remove, clean and tighten down. Recheck power to ecu. Check the ground at ecu and at t-stat housing with continuity tester and see if you have continuity. if you do, then you have a good ground.
since you do not get power to the ecu with the key on ignition 2, does the ecu get power when cranking the engine?
let me know what you find.
did you actually check for power at the ecm with a dvom? you should have 1pin with constant power and 1 with keyed power
if so, have you checked your ecm ground pins? i believe there should be 3
if so, you checked the fuse panel underhood, yes?