check engine light not working on 1990 Nissan Pickup (D21)

My son just bought his first vehicle which failed CA smog because the check engine light does not come on. What can we do to fix this?

Asked by for the 1990 Nissan Pickup (D21)
1 answer
take it to a shop and have them check the system. it may be a bulb, fuse or failed computer.

Roy