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Been trying to play around with these for a while now and get a better understanding of how they work.
Have had an interesting failure on the bench so thought I'd post it up in case other people have had similar problems.
ECU has been played with on the bench and re flashed with HPTuners a number of times as well as playing with it using Tazzi's Software on ELMStreet.
Was all going well until yesterday when I turned on ignition switch on the bench and it wouldn't power up. Left it for a while and same thing, checked power supply switch, everything fine.
Plugged it back in and turned on power supply, had left ignition switch on and it all powered up fine. Turned ignition off, waited for it to go to sleep, ignition back on, won't work. Turned power supply off, ignition on, powered up and all good again.
I'm suspecting I've damaged a transistor or something in the ECU.
I'm also thinking it may pay to run an additional ground wire to earth the ECU case as per engine install in future. Wondering if I may have pulled to much current through it just using bench harness to the terminals.
Yoda69

I've litterally done 100 read/write's & various mucking around on VZ E55 with my bench harness/PSU setup, it's not a high amp rated PSU (supposedly not even enough for E69 & E77 on the bench for TIS, but with HPT it work's fine so go figure). But no I've never had an issue like that & sometimes had ECU powered up for hours & forgot while side tracked in the workshop, sorry I can't be of more help.

ive been playing around with VZ pcm on the bench too... getting an understanding of the flashing process. mine is earthed through the ecu case only. had it powered up for days at a time

I've accidentally left mine powered on the bench for a day or two. Gets pretty warm. Mines grounded through the case. Also have a beefy PSU hooked up.

mines got 12v from the hard drive connector hanging out my open PC case........ use it for all my bench pcms

My power supply shouldn't be a problem, set at 13.7v and ecu powered up shows around 0.3 to 0.4 amps.
Think from now on I'll be using an additional earth direct to ECU case just to make sure. Have done heaps of playing on the bench without issue to now, so fairly robust, may have just been bad luck.

When it's powered up OK, maybe you should read the bin and check for corruption.

Joe.

yoda69 wrote:My power supply shouldn't be a problem, set at 13.7v and ecu powered up shows around 0.3 to 0.4 amps.
Think from now on I'll be using an additional earth direct to ECU case just to make sure. Have done heaps of playing on the bench without issue to now, so fairly robust, may have just been bad luck.

Nah, quite common, seems these ecus "lock" them selves up. When I power the unit up the first time, its all good and communicates fine. But if I turn off the power then back on and try and communicate.. nothing.
I have to complete disconnect the power+ground wires from the ecu then reconnect to get the ecu communicating again

Now, these ecus are meant to be "dead" ecus, where the scantool will say "Cant communicate with vehicle". But, they work great right now! I wonder if this is the infamous issue with these ecus.. where if they lose power.. it causes them to lockup somehow until completely removed?

Thoughts anyone?

j_ds_au wrote:When it's powered up OK, maybe you should read the bin and check for corruption.

Joe.

Wouldnt be intermittent if the ecu was corrupt. It will just stay dead.. as a door nob.. with lots of confusion for hours... haha.

I attempted to reprogram an E55 using tis2web. The ecu was on the latest version for its calibration.. so.. being the tinkerin type... I manually entered a different vin and flashed a different VZ E55 bin into the ecu.
It failed at the 99% (possibly 100%). Soooo. I entered the original vin.. tried flashing back to original ecu bin. But failed again about 20% in. So I bit the bullet and turned off the power.
Then disconnected ecu, reconnected and powered up. And it continued communicating! All was good, until 1min later I turned off power, repeated disconnect procedure.. fired her up.. and nothing.. absolutely nothing.. and still sits on the bench as a fancy paperweight.

Lesson learnt.. never flash the wrong OS calibration ID into the ecu!

I haven't had the non communicating issue with bench tinkering yet & I just have ALL ecu's earthed through sensor earth wires, but I guess for fail safe an earth on case is a good thing to have.

With flashing wrong OS on the E55's I think there ALL interchangeable but need to do a write entire if changing to a different OS/cal, but thats a completely different story for the E69, E77 & possibly E38.

VX L67 Getrag wrote:I haven't had the non communicating issue with bench tinkering yet & I just have ALL ecu's earthed through sensor earth wires, but I guess for fail safe an earth on case is a good thing to have.

With flashing wrong OS on the E55's I think there ALL interchangeable but need to do a write entire if changing to a different OS/cal, but thats a completely different story for the E69, E77 & possibly E38.

Hmmm.. pretty sure SPS was doing an entire flash. Not sure why it failed, the PSU has plenty of juice to pump into it if needed. And all connections were strong.

I have both a ground from the ecu ground pin, as well as another direct off the casing. Better safe then sorry