Up-Shift Light; Brake System Warning Light - GMC Jimmy 2004 Owner's Manual

You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.

Up-Shift Light

Shifting when the indicator light is on will help you get
the best fuel economy. See "Up–Shift Light" under
Manual Transmission Operation on page 2-28.
3-28
You have the shift light
if you have a manual
transmission.

Brake System Warning Light

When the ignition is on, the brake system warning light
will come on when you set your parking brake. The
light will stay on if your parking brake doesn't release
fully. If it stays on after your parking brake is fully
released, it means you have a brake problem.
Your vehicle's hydraulic brake system is divided into two
parts. If one part isn't working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on, there could be a brake
problem. Have your brake system inspected right away.
United States
This light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then, have it
fixed so it will be ready to warn you if there's a problem.
Canada