ecu problem may be solved, please confirm or discuss

[dr1ft-pig]

hey all, the guys who read my other tech Q would know ive blown 3 adaptronics now... anyway

i set to it this arvo and started pulling the tape off my wiring loom, now the part in the ecu that keeps frying itself is 2 diodes on the circuit that runns my vvti, this afteroon i have learned that my 2 vvti plugs share an earth so i checked continuity, the conection that branches said shared earth into each vvti plug had good contiuity between it and the plugs and also between that same conection and the pinout, then when i checked continuity between that same conection and the body/battery earth i had the shittiest continuity ever so im guessing its a poor earth thats causing it to keep frying, but what has me stumped is if those 2 diodes are fried then maybe thats why its getting poor earth?? though im not sure if those diodes are on the positive or negative side of the circuit, if they are on the positive side i should be getting a great earth correct??

so im thinking, this setup lasted 12 months in ants car and ive had it 9 months in mine and gone through 3 ecus.... when i put the gear in mine nothing changed in the loom, all i did was power up the ecu so its quite possible i havent earthed it correctly or my car just has poor earthing in general therefore giving the ecu a poor earth...

what should i do to fix it apart from going over all the earths and possibly adding a few more just to give it a bit better earth???

cheers to those who read the fucking novel i just wrote haha

[Phife]

My guess is if the ecu doesn't already have a common ground wire feeding it, then it would be the ecu box itself acting as ground supply. Check the resistance between it and the chassis.
The vvti requires a +ve signal, a poor GND return line will create problems. Without knowing the ecu schematics i would guess they were on the +ve side.
A simple upgrade in general is to put larger ground cables on everything.
Hope this helps.

[dr1ft-pig]

that basicaly confirms it mate, cheers, gonna take off every gnd wire and clean surfaces and add earths etc tomorro


still need a new ecu but hahha

thanks bud

[Anthony]

Please dont add earths that arent meant to be there

Like I said last time, theres no comon earth. like most automotive switches, its a switched earth at the ecu, the common youre measuring is ignition 12V, so I hope it has little continuity to ground

I have organised a fix for this and will be in touch soon, just a bit hard with xmas/new year.

Dont forget to mention that you were given a brand new ecu free of charge last time

[dr1ft-pig]

only earth ive added is from where the loom itself earths to the engine, iv added one from there to the body...

yeah cheers heaps.. been tryin to get onto you for ages

indeed i was.. muchly appreciated, that and all the help you have given me with the car

look forward to hearing from you... need to get her fired up again so i can get me up to brissy

i shall also talk to you about that turbo kit when i talk to you next