why does check engine light keep coming on after computer replaced

Question

Brought Honda Accord 2000…into dealer due to check engine light was on…
they gave me a Honda distributed paper from 2005 that said it was typical that the sensor was faulty….so they replaced the computer….800. dollars…+ labor
Drove car several hundred miles….had a smog test….all went well…
Then check engine light came on again….neighbor checked it …the coolant was low in the reservoir…we filled it …he turned off light….several days later….the light comes back on…??
Now what??

Answer 1

P1486 Cooling system malfunction

Has the cooling system pressure tested, there a coolant leak.