A Chilton's manual will have the schematics that you need.
what does a low battery light look like on a 2001 Saturn
power = light green ground = black
P21/5w
how to use bcm to reset change oil light
You need coolant.
You can program the keyless entry remote, for your 2001 Saturn L200, by holding the unlock and lock weapons at the same time. The red light will flash on and off. The remote will be programmed when the red light stays illuminated.
Check your coolant level
There is no external timing marks on 2001 Saturn.
Black with Orange trace
What is the torque spec for a 2001 Saturn head? It has only a single cam
were is crankshaft sensor located in 2001 Saturn l300
There are pages and pages of things that can cause a check engine light. You need to have it checked with a scantool. Then the code can be diagnosed and repaired.