No power to ECU
#1
Displacement Replacement
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Location: St. Thomas
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No power to ECU
I've been having some problems with my FD the last week or so, it runs good then will just shut right off , the tach and everything goes dead, it'll take a minute or 2 then it will start back up , the last couple days everytime i would go to drive it , it would happen , today i went to move it out of the way to get my other car out, started it up warmed it up for a minute then it shut off and wont start.
I've been going over everything trying to figure out whats wrong. I have no spark,I have an AFC neo hooked up for well over a year with no issues. but its not powering on either so im thinking the ecu must not be getting any power or something
so far this is what i've done.
Tried a different igniter
checked all my fuses under the hood and the engine fuse under the dash
checked the plugs and wiring at the CAS
tested the EGI relay
im not sure if my AFC neo just died and is keeping it from starting but doesnt really seem that likely since i have no spark either
it really sucks because my only other working car is blocked in by my FD and my driveway is sloped onto a busy narrow street so i cant just push it out on the road lol
I just went out and tested my afc to see if it powered on with 12v and it works , so im not getting power to my ecu
I've been going over everything trying to figure out whats wrong. I have no spark,I have an AFC neo hooked up for well over a year with no issues. but its not powering on either so im thinking the ecu must not be getting any power or something
so far this is what i've done.
Tried a different igniter
checked all my fuses under the hood and the engine fuse under the dash
checked the plugs and wiring at the CAS
tested the EGI relay
im not sure if my AFC neo just died and is keeping it from starting but doesnt really seem that likely since i have no spark either
it really sucks because my only other working car is blocked in by my FD and my driveway is sloped onto a busy narrow street so i cant just push it out on the road lol
I just went out and tested my afc to see if it powered on with 12v and it works , so im not getting power to my ecu
#3
Any resolution here? My car is having a similar issue just recently. It It started cutting out randomly while driving but then went away. Only to completely die at a stoplight later that day and not restart. It appears the ECU isn't getting any power, cannot connect to it with my computer.
#4
Best to get a copy of the wiring diagram and also find the ECU pinout diagram thats floating around somewhere on here.
1. Double check the ECU earth/ground strap is clean and tight and is not corroded or loose.
If OK, proceed to:
2. Consult the ECU plugs pinout diagram. Find the main B+ power feed pin.
3. Get the wiring diagram for the car. Trace the B+ power wire for the ECU to the nearest connector. Verify connector is plugged together tightly and looks fine. Keep chasing the B+ power along the wiring diagram until you locate a problem.
If no problems found in power feed wiring to the ECU:
4. Remove ECU. Fit a borrowed "known good working ECU" to the car and verify that it runs.
If it runs after completing step 4: Your ECU is likely faulty internally.
1. Double check the ECU earth/ground strap is clean and tight and is not corroded or loose.
If OK, proceed to:
2. Consult the ECU plugs pinout diagram. Find the main B+ power feed pin.
3. Get the wiring diagram for the car. Trace the B+ power wire for the ECU to the nearest connector. Verify connector is plugged together tightly and looks fine. Keep chasing the B+ power along the wiring diagram until you locate a problem.
If no problems found in power feed wiring to the ECU:
4. Remove ECU. Fit a borrowed "known good working ECU" to the car and verify that it runs.
If it runs after completing step 4: Your ECU is likely faulty internally.
#5
Form follows function
iTrader: (8)
I had the exact same problem whereas the ecu fell to less than 5v. The problem turned out to be a harness wire where it attached to its pin at the ecu connector--it was severely corroded by a chemical that had leached from the wire's insulation.
In any event, check the main pwr (1B iirc) and main ground pins very carefully. They can be released from the housing for surgery if needed.
Good luck
In any event, check the main pwr (1B iirc) and main ground pins very carefully. They can be released from the housing for surgery if needed.
Good luck
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