Charging System Warning Light; Malfunction Indicator (Service Engine Soon) Lamp - GMC SIERRA 1995 Manual

Charging System Warning Light
The red Charging System Warning light should come on briefly when you
turn on the ignition, before starting the engine, as a check to show you it is
working. After the engine starts, the light should go out. If it stays on or
comes on while you are driving, you may have a problem with your
charging system. It could indicate a problem with the alternator drive belt,
or some other charging system problem. Have it checked right away.
Driving while this light is on could drain your battery.
If you must drive a short distance with this light on, it helps to turn off all
your accessories, such as the radio and air conditioner.
Malfunction Indicator (Service Engine Soon) Lamp
I
A computer monitors the operation of your fuel, ignition and emission
control systems. This orange light should come on when
the
ignition is on
but the engine is not running. as a check to show you it's working. If
it
does
not come on at all, have it fixed right away. If
it
stays on, or comes on while
you are driving, the computer is indicating that you have a problem. You
should take your vehicle in for service soon.
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