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. Crankshaft Main Bearing Clearance Measure
Method A
1.
Measure the crankshaft bearing journal
diameter with a micrometer in several places, 90 degrees apart.
Average the measurements.
2.
Measure the crankshaft bearing journal
taper and runout.
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