check engine light CHEVROLET C/K 2003 Owner's Manual

6-56 Automatic Ether Injection System
(If Equipped)
If you have a Caterpillar
diesel engine, you may have
this feature. The ether
cylinder is located in the
engine compartment on the
driver's side of the vehicle.To change an empty ether cylinder, follow these steps.
1. Loosen the screw head on the cylinder
-to-bracket
clamp.
2. Spread the clamp apart.
3. Clean any dirt from the neck of the cylinder and the
top of the valve before you take out the cylinder.
4. Check the inside of the valve for any foreign matter.
Clean the valve as necessary.
5. Cover the valve to protect it from dirt and take out
the cylinder.
6. Install a new gasket whenever you take out the
cylinder. Use only one gasket and spread a light film
of clean oil on it before installation.
7. Put in the new cylinder. Turn it clockwise until it just
starts to contact the gasket.
8. Tighten the cylinder another half turn (180 degrees).
Don't over
-tighten.
9. Retighten the cylinder clamp.

6-78 Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the light switch. An electrical overload will cause the
lights to go on and off, or in some cases to remain off.
If this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker inside the motor and a circuit breaker or fuse in
the fuse block. If the motor overheats, the wipers will
stop until the motor cools. If the overload is caused by
an electrical problem, be sure to get it fixed.
Fusible Links
A fusible link is a short piece of wire several gauge sizes
smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation is
burned beyond recognition, consult your GM dealer for
the proper size. Replace a fusible link with one of the
same size and insulation type. Fusible link insulation is a
special purpose high
-temperature material.
The hydraulic brake booster motor feed circuit and
starter circuit are protected by a fusible link. Vehicles
with a diesel engine have a fusible link for the intake
heater feed circuit.

7-16
Footnotes

= The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
(1) = If your vehicle has an Allison automatic
transmission, your GM owner's manual is supplemented
by an Allison Transmission Operator's Manual. Always
refer to these manuals for related maintenance services.
(2) = Refer to the Caterpillar Diesel Engine Operation
and Maintenance Manual for oil recommendations and
change intervals.
(3) = An Emission Control Service.
(4) = A Noise Emission Control Device.
(5) = Applies only to vehicles sold in the United States.(6) = Check fluid level in brake master cylinder, power
steering pump, axle, transmission and hydraulic spring
parking brake pump (if equipped). A low fluid level in
the brake master cylinder can indicate worn brake
linings and should be checked accordingly.
(7) = Inspect brake lines and hoses for proper hook
-up,
binding, leaks, cracks, chafing, etc. Inspect disc brake
pads for wear and rotors for surface condition. Inspect
caliper assemblies. Check brake pedal for excessive free
play or travel (or every 6 months, whichever occurs first)
and have serviced if needed. Check brakes more often if
driving habits and conditions result in frequent braking.
(8) = Inspect parking brake drum and linings for wear or
cracks and check linkage and adjustment.
(9) = This vehicle has the GM Oil Life System. This
system will show you when to change the engine oil and
filter
-- usually between 3,000 miles (5 000 km) and
7,500 miles (12 000 km) since your last oil change.
Under severe conditions, the indicator may come on
before 3,000 miles (5 000 km). Never drive your vehicle
more than 7,500 miles (12 000 km) or 12 months
without an oil and filter change.
Remember to reset the Oil Life System whenever the oil
is changed. For more information, see ªChange Oil
Lightº in the Index.

7-22 At Least Twice a Year
Restraint System Check
Make sure the safety belt reminder light (if equipped)
and all your belts, buckles, latch plates, retractors and
anchorages are working properly. Look for any other
loose or damaged safety belt system parts. If you see
anything that might keep a safety belt system from
doing its job, have it repaired. Have any torn or frayed
safety belts replaced.
Wiper Blade Check
Inspect wiper blades for wear or cracking. Replace blade
inserts that appear worn or damaged or that streak or
miss areas of the windshield. Also see ªWiper Blades,
Cleaningº in the Index.Engine Air Cleaner Filter Restriction
Indicator Check
Your vehicle has an indicator located on the air cleaner
in the engine compartment that lets you know when the
air cleaner filter is dirty and needs to be changed. Check
indicator at least twice a year or when your engine oil is
changed, whichever occurs first. See ªEngine Air
Cleanerº in the Index for more information. Inspect your
air cleaner filter restriction indicator more often if the
vehicle is used in dusty areas.
Weatherstrip Lubrication
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather more frequent application may be
required. See ªRecommended Fluids and Lubricantsº in
the Index.