Service Engine Soon light question?

[2_wacko]

After doing a frame swap on my 87 truck I noticed the SES light come's on when I start it up, but when I turn the head lights on the SES light turn's off? Is this normal or is something wrong?

 

[2_wacko]

Figured it out thanks.

 

[Terminal4]

just curious, what was the issue? i was going to suggest to take it to your local chevy dealership, jk.