S300 Red Led : communication issue ?

[Isofouet]

Hi,

A friend of mine has a problem with his S300 : a red led appeared and the car (EK3 swapped with a B18) runs very badly (poor idle, knocks, etc)

It appeared one day, there were no real weak signals before...

I read some topics that said that uploading a stock map and then the tuned map can solve the problem.
It worked indeed the first time, and the led switched to green.

But the next morning, the red led came back...

So I check the ECU : no damaged components, socketing is OK (modifications are done, no broken pin, etc)

So we tried the same method but it didn't worked...
It seems that the S300 has a communication problem with the ECU : Indeed, no matter the map I upload (stock, tuned ...), there were no changes on the engine behaviour.
The ECU seemed to be in limp mode...

So I took off the S300 from the ECU, checked one more time the socketing, and reinstalled it.
And miracle came : the LED was green, and everything was working fine !

So we supposed that the cold weather could have an influence : we took the ECU off yesterday, and stored it a a warm place for the night...
This morning, the LED was still green, everything was OK

But at noon, the red led came one more time... (the car was parked outside this morning)


What do you think of this issue ? Could it be a S300 failure ?

Thank you

[Hondata]

It is common to experience problems with solder joints when the weather is cold if they are not 100% good. Touch up all the solder joints on the connector with fresh solder.