Thread: ECU Buzz

I am almost done with my T28 DE+T install. Put in my JWT ECU and relo'd the battery to the trunk. Now the ECU is buzzing when when the car is turned to on. It will stop once the battery is disconnected. I have replaced the ECU, Brand new battery and changed the ground from the trunk and used a jumper back to the stock ground under the hood and still buzzes. Car will just keep turning over and wont start.

Any clues? Thank you-

Power to the ECCS relay could be insufficient.

Well I bought a new relay and still the same thing although the buzz was a little more quiter. Fuel pump is still not kicking on. I have swapped out my JWT with my old G20 ECU and still the relay is buzzing.

So I can say the ECU is fine, I have regrounded the battery in 2 different places.

Should I run a jumper wire to power the ECCS relay to see if that stops it? Thanks for the help!

with a test light. check for 12v on the relay.you should get two 12v going to the relay. both switch and a constant 12v.
also with the test light check the fuel pump conector with the ignition on to see if you getting a 12v. if yes put the test light wire to 12v and test the fuel pump connector ground. that should narrow down your problem.

I HAD THE SAME PROBLEM WITH A R1 BIKE AND IT WAS A LOOSE CONECTOR.

Thanks Perry, I will try this out on Saturday...

Ran the voltage check and checking out at 11.5 (I have been cranking on the battery so that may be why its not over 12v). I think it is a ground issue, I am blowing my engine control 7.5a fuse under the hood. I replaced it, turned the key to on, the fuel pump kick on, the eccs relay stopped buzzing and then "pop", blew the fuse.

Now I need to check where the ground issue is at....Will start at the fuel pump and every other ground that I can find.

Had some time to start the search and it looks like pin 19 & 39 (both ECU grounds) have no continuity all other grounds are good. I will check all grounds under the hood.

Also the tach is jumping around when the ECCS relay is buzzing. Check main grounding points (by each headlight and 2 at the top of the intake) cleaned them all and regrounded, no help. Must be a wire inside the loom that is open or frayed?

hey still have that problem? i thing you should bench test the fuel pump. take it out and give it a ground and a 12 v direct to see if it dont jam from sitting long without working.sometime if it jam the load could be to much on the fuse thats why it blowin it.