hi guys i installed a yellow box on my car a few days ago and i disconnected the unit while the key was still in pos I, a few seconds later i start the car and the battery light comes on. i instantly turn the car off and on and it goes away. now everytime i start up the battery light does not show anymore??? help

 

come again?

 

Where did you take power from? Where did you ground? Where did you hook up the speed signal intercept wiring?
I would suspect you've wired something to the wrong place.

 

the earth was to an existing point on the chassis that was already there. the 12v was to the fuse box constant plug. and the others were to the VSS wire near the ecu.

@Wisconsin S2k
my battery icon on dash does not appear when i turn my keys to the II position, when it should do.

 

I'm can't say for sure that these are what is causing your problem but ...............

Power should not be "constant". It should come from the tap that is HOT with ignition. You don't want the YB to be powered all the time. Also, it needs to be powered off to reset itself each time you re-calibrate (when first putting this in service).
There are two locations near the ECU that has the same colored wire for the speed sensor. ONLY one of these is correct. Many have used the wrong one and have run into weird problems.

 

thanks for that. i'l try and wire it to an ign live. thanks again

 

i disconnected the yellow box and the battery light is still not comming on. anymore suggestions???

 

The only thought I have left on this is that possibly, the connection to the VSS wire at the ECU was not the correct one and using the wrong one may have blown a circuit. Or, you haven't properly reconnected the two ends of the wire you cut.
Maybe this drawing will help you even though I did mine at the tranny speed sensor. The principle is the same: