B16 Swap CEL Question

[Varao]

My buddy just put in a B16A into his 5th gen Civic DX. Everything looks fine and works great until he runs it for awhile a CEL will come on. But if you shut her down and turn her back on no CEL. Also with the jumper no CELs are shown. The CEL dosent come on when Vtec hits or at a certain RPM or temp. So I am confused on where to look even is there a way to see what that CEL is? As always any and all help is greatly appreciated thanks!

[HONDA GHANDI]

If it has no CEL when the jumper is installed it is normally a bad ECU or bad ECU ground/power wire. The CEL resets itself every time you cycle the key so it sounds like something along those lines. WHat is the ECU part number?

[floored4door]

Is the ground on the Thermo good and tight?

[Varao]

Ghandi: The ECU is the stock JDM ECU that came with the swap from H-motors I am unsure of the # but its the stock OEM one. I know he relocated the battery into the trunk before the swap perhaps its something to do with that?

Pete I will check the ground on the thermo switch.

Thanks for the leads guys I do appreciate the help!!

[Varao]

Well we re-ran the battery and the ECU seems to have everything it needs but the CEL still will not stay. IT throws it after it hits operating temp, the car does not sound or feel like its wrong in anyway. He also installed a Teg sized radiator with an aftermarket fan. The thermo switch seems to be hooked up right. Any and all help is appreciated!!

[HONDA GHANDI]

Without a code there is no way to diagnose it over the internet. Try a known good ecu.

[Varao]

Thanks Tobi man I appreciate it!

[HONDA GHANDI]

No probby.