This light comes on briefly
when the ignition is turned
on, and the engine is not
running, as a check to
show it is working. Then it
should go out when the
engine is started.
If the light stays on, or comes on while driving, there may be a problem with the electrical charging system.
Have it checked by your dealer/retailer. Driving while this light is on could drain the battery.
If a short distance must be driven with the light on, turn off all accessories, such as the radio and air conditioner.
Chevrolet Cobalt Service & Repair Manual. Compression Pressures
1.
Ensure engine is at room temperature
and battery is fully charged.
2.
Disconnect wiring from ignition module
and remove spark plugs.
3.
Throttle body valve should be wide
open.
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