Hello guys.
I experience a problem with one of my S300 boards

Calibration is for test a new p30 usdm file uploaded after erased s300
Using two ecu a p28 and a P30 both with new replaced capacitors in perfect working condition with other s300 v3 board.

The problem is that the ecu is not comunicate with s300 board which result to no datalog and 4000rpm rev limit.

When turn the key on the D3 led on the s300 stay on for a second and then shut off.
If ecu has communication with s300 board D3 led should stay on all the time.
Thats how an other s300 v3 board i have is working.
The problem is not from the socketing as did all the necessary tests for continuity with multimeter.
I have an other s300 v3 board which i tried and it worked perfect at the same ecu.
I also tried the faulty s300 board on the other known good ecu with same results.
Tested both on car and on engine simulator with same results.
I removed the vin sticker to check the tracks for continuity under it. I still have it btw.

Does anyone know a way to reset the firmware on S300 ?
If it is not a firmware issue then it must be a hardware component.
Does anyone have a similar problem to point me to a solution to fix it ?

Here is a video sawing the problem.
https://youtu.be/sT5ZcRyoVl0

 

Are you certain that the board is on the headers correctly. I know it sounds stupid but sometimes its not pressed all the way in fully and youll be in limp mode.

 

Yes it is sitting properly.
Also i checked the continuity with multimeter from the bottom of the ecu pins to to the top of the s300 board and have continuity.
It is not in limp mode as the car have 450cc injectors and it is working fine until 4000rpm.
If it was in limp mode with these injectors it can not even start ,it floods every cylinder.
It looks like firmware problem as it have 4000rpm rev limit and no datalog.
I see some other s300 owners have the same problem at forums but most of the time the cause of the problem or the solution not published.

 

I don’t mean to thread jack but I’m having the same problem the d3 light flicks on for a secon I’ve tried 4 ecus and replaced all the fuses and interior main harness I’m not able to upload or datalink but the board says everything is normal on the laptop

 

In my case it was a faulty s300 board or the internal firmware of the board.
I make contact with hondata support and send them the ecu for inspection and RMA.
In your case i would try a new usb cable and then with new cable try erase the ecu and upload a new stock file to see if this fixes the upload failure and maybe also the datalog.
After my case will finaly end i will post here what was the cause and the process for future info.

 

I’ve talked to there support but they keep telling me it’s the capictors but I’ve tried 4 ecus when I go to the erase ecu menu it’s grayed out so I can’t select it I’m thinking it’s gotta be the board do you know what there gonna charge for a new board

 

Did you try an other good known usb cable ?
I had a problem simmilar with you in the past and it was the cable.
Any of these ecu you tested need new capacitors as they are more than 25years old with life for 10years.
So if i was you i would first replace the capacitors and if not fix it then try a new cable.

With Smanager open and ecu connected does it show at the bottom left corner of the screen the s300 to be online and drivers installed ?
I do not know the cost for a replacement board.

 

Yes it’s showing online and it shows the screen just like the pic you posted the usb cord seems to be connected it’s able to power on the board with just the laptop

 

Test an other cable

 

Cable ordered I’ll reply when I test it out

 

You can test any usb cable from desktop printer.
But a new good quality with ferrite beads for filter is better of course.