2009 CHEVROLET TAHOE display

TRAILER GAIN – This setting is displayed anytime the
Trailer Brake Display Page is active. This setting
can be adjusted from 0.0 to 10.0 with either a trailer
connected or disconnected. To adjust the Trailer Gain,
press one of the Trailer Gain adjustment buttons
located on the Trailer Brake Control Panel. Press and
hold a gain button to cause the Trailer Gain to
continuously adjust. To turn the output to the trailer off,
adjust the Trailer Gain setting to 0.0 (zero).
0.0 (zero) gain is the factory default setting. To properly
adjust trailer gain, see the Trailer Gain Adjustment
Procedure later in this section.
TRAILER OUTPUT – This is displayed any time a trailer
with electric brakes is connected. Output to the electric
brakes is based on the amount of vehicle braking
present and relative to the Trailer Gain setting. Output is
displayed from 0 to 10 bars for each gain setting.
The Trailer Output will indicate “------’’ontheTrailer
Brake Display Page whenever the following occur:
No trailer is connected.
A trailer without electric brakes is connected (no
DIC message is displayed).
A trailer with electric brakes has become
disconnected (a CHECK TRAILER WIRING
message will also be displayed on the DIC).
There is a fault present in the wiring to the electric
trailer brakes (a CHECK TRAILER WIRING
message will also be displayed on the DIC).
There is a fault in the ITBC system (a SERVICE
TRAILER BRAKE SYSTEM message will also
be displayed in the DIC).
Manual Trailer Brake Apply
The Manual Trailer Brake Apply Lever is located on the
Trailer Brake Control Panel and is used to apply the
trailer’s electric brakes independent of the vehicle’s
brakes. This lever is used in the Trailer Gain Adjustment
Procedure to properly adjust the power output to the
trailer brakes. Sliding the lever to the left will apply only
the trailer brakes. The power output to the trailer is
indicated in the Trailer Brake Display Page in the DIC. If
the vehicle’s service brakes are applied while using
the Manual Trailer Brake Apply Lever, the trailer output
power will be the greater of the two.
The trailer and the vehicle’s brake lamps will come on
when either vehicle braking or manual trailer brakes are
applied.
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Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specic trailering
condition and must be adjusted any time vehicle loading,
trailer loading or road surface conditions change.
Setting the Trailer Gain properly is needed for the best
trailer stopping performance. A trailer that is
over-gained may result in locked trailer brakes. A trailer
that is under-gained may result in not enough trailer
braking. Both of these conditions may result in poorer
stopping and stability of the vehicle and trailer.
Use the following procedure to correctly adjust Trailer
Gain for each towing condition:
1. Make sure the trailer brakes are in proper working
condition.
2. Connect a properly loaded trailer to the vehicle and
make all necessary mechanical and electrical
connections. SeeLoading the Vehicle on page 4-33
for more information.3. After the electrical connection is made to a trailer
equipped with electric brakes:A TRAILER CONNECTED message will be
briey displayed on the DIC display.
The Trailer Brake Display Page will appear on
the DIC showing TRAILER GAIN and TRAILER
OUTPUT.
In the Trailer Output display on the DIC, “------’’
will disappear if there is no error present.
Connecting a trailer without electric brakes will not
clear the six dashed lines.
4. Adjust the Trailer Gain by using the gain adjustment
(+ / -) buttons on the Trailer Brake Control Panel.
5. Drive the vehicle with the trailer attached on a level
road surface representative of the towing condition
and free of traffic at about 20 to 25 mph (32 to
40 km/h) and fully apply the Manual Trailer Brake
Apply lever.
Adjusting trailer gain at speeds lower than 20 to
25 mph (32 to 40 km/h) may result in an incorrect
gain setting.
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6. Adjust the Trailer Gain to just below the point of
trailer wheel lock-up, indicated by trailer wheel
squeal or tire smoke when a trailer wheel locks.
Trailer wheel lock-up may not occur if towing
a heavily loaded trailer. In this case, adjust the
Trailer Gain to the highest allowable setting for the
towing condition.
7. Re-adjust Trailer Gain any time vehicle loading,
trailer loading or road surface conditions change
or if trailer wheel lock-up is noticed at any time while
towing
Other ITBC Related DIC Messages
In addition to displaying TRAILER GAIN and TRAILER
OUTPUT through the DIC, trailer connection and
ITBC system status is displayed in the DIC.
TRAILER CONNECTED – This message will be briey
displayed when a trailer with electric brakes is rst
connected to the vehicle. This message will
automatically turn off in about ten seconds. The driver
can also acknowledge this message before it
automatically turns off.CHECK TRAILER WIRING – This message will be
displayed if:
1. The ITBC system rst determines connection to a
trailer with electric brakes and then the trailer
harness becomes disconnected from the vehicle.
If the disconnect occurs while the vehicle is
stationary, this message will automatically turn off in
about thirty seconds. This message will also turn
off if the driver acknowledges this message off or if
the trailer harness is re-connected.
If the disconnect occurs while the vehicle is moving,
this message will continue until the ignition is
turned off. This message will also turn off if the
driver acknowledges this message off or if the trailer
harness is re-connected.
2. There is an electrical fault in the wiring to the
electric trailer brakes. This message will continue as
long as there is an electrical fault in the trailer
wiring. This message will also turn off if the driver
acknowledges this message off.
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To determine if the electrical fault is on the vehicle side
or trailer side of the trailer wiring harness connection,
do the following:
1. Disconnect the trailer wiring harness from the
vehicle.
2. Turn the ignition OFF.
3. Wait ten seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message
re-appears, the electrical fault is on the vehicle side.
If the CHECK TRAILER WIRING message only
re-appears when connecting the trailer wiring
harness to the vehicle, the electrical fault is on the
trailer side.
SERVICE TRAILER BRAKE SYSTEM – This message
will be displayed when there is a problem with the
ITBC system. If this message persists over multiple
ignition cycles there is problem with the ITBC system.
Take the vehicle to an authorized dealer/retailer to have
the ITBC system diagnosed and repaired.If either the CHECK TRAILER WIRING or SERVICE
TRAILER BRAKE SYSTEM message is displayed while
driving the vehicle, power is no longer available to
the trailer brakes. When traffic conditions allow, carefully
pull the vehicle over to the side of the road and turn
the ignition off. Check the wiring connection to the
trailer and turn the ignition back on. If either of these
messages continues, either the vehicle or trailer needs
service.
An authorized dealer/retailer may be able to diagnose
and repair problems with the trailer. However, any
diagnosis and repair of the trailer is not covered under
the vehicle warranty. Please contact your trailer
dealer for assistance with trailer repairs and trailer
warranty information.
4-65

When replacing the fuel cap, insert the tether in its hole
before tightening the cap. Turn the fuel cap clockwise
until it clicks. It will require more effort to turn the fuel cap
on the last turn as you tighten it. Make sure the cap is
fully installed. The diagnostic system can determine if
the fuel cap has been left off or improperly installed.
This would allow fuel to evaporate into the atmosphere.
SeeMalfunction Indicator Lamp on page 3-43.
If the vehicle has a Driver Information Center (DIC), the
TIGHTEN GAS CAP message displays if the fuel
cap is not properly installed.
{CAUTION:
If a re starts while you are refueling, do not
remove the nozzle. Shut off the ow of fuel by
shutting off the pump or by notifying the station
attendant. Leave the area immediately.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer/retailer can get one
for you. If you get the wrong type, it may not t
properly. This may cause the malfunction indicator
lamp to light and may damage the fuel tank and
emissions system. SeeMalfunction Indicator Lamp
on page 3-43.
5-11

How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use. Whenever
the oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where the oil is changed prior to a CHANGE ENGINE OIL
SOON message coming on, reset the system.
Always reset the engine oil life to 100% after every oil
change. It will not reset itself. To reset the Engine
Oil Life System:
1. Display the OIL LIFE REMAINING on the DIC. If
the vehicle does not have DIC buttons, the vehicle
must be in P (Park) to access this display. See
DIC Operation and Displays (With DIC Buttons) on
page 3-52orDIC Operation and Displays (Without
DIC Buttons) on page 3-58.
2. Press and hold the SET/RESET button on the DIC,
or the trip odometer reset stem if the vehicle does
not have DIC buttons, for more than ve seconds.
The oil life will change to 100%.
If the CHANGE ENGINE OIL SOON message comes
back on when the vehicle is started, the Engine Oil Life
System has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Recycle it by taking it to a
place that collects used oil.
5-19

3. With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, move the
shift lever back to P (Park).
4. Allow the engine to idle (500 – 800 rpm) for at least
one minute. Slowly release the brake pedal.
5. Keep the engine running and press the Trip/Fuel
button or trip odometer reset stem until TRANS
TEMP (Transmission Temperature) displays on the
Driver Information Center (DIC).
6. Using the TRANS TEMP reading, determine and
perform the appropriate check procedure. If the
TRANS TEMP reading is not within the required
temperature ranges, allow the vehicle to cool,
or operate the vehicle until the appropriate
transmission uid temperature is reached.Cold Check Procedure
Use this procedure only as a reference to determine if
the transmission has enough uid to be operated
safely until a hot check procedure can be made. The
hot check procedure is the most accurate method
to check the uid level. Perform the hot check procedure
at the rst opportunity. Use this cold check procedure
to check uid level when the transmission temperature is
between 80°F and 90°F (27°C and 32°C).
1. Locate the transmission
dipstick at the
rear of the engine
compartment, on the
passenger side of the
vehicle.
SeeEngine Compartment Overview on page 5-14
for more information.
2. Flip the handle up, and then pull out the dipstick
and wipe it with a clean rag or paper towel.
3. Install the dipstick by pushing it back in all the way,
wait three seconds, and then pull it back out again.
4. Check both sides of the dipstick and read the lower
level. Repeat the check procedure to verify the
reading.
5-23

If No Steam Is Coming From The
Engine Compartment
The ENGINE OVERHEATED STOP ENGINE or the
ENGINE OVERHEATED IDLE ENGINE message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on page 4-50.
If you get the ENGINE OVERHEATED STOP ENGINE or
the ENGINE OVERHEATED IDLE ENGINE message
with no sign of steam, try this for a minute or so:
If the overheat warning is displayed with no sign of
steam:
1. Turn the air off.
2. Turn the heater on to the highest temperature and
to the highest fan speed. Open the windows as
necessary.
3. In heavy traffic, let the engine idle in N (Neutral)
while stopped. If it is safe to do so, pull off the
road, shift to P (Park) or N (Neutral) and let
the engine idle.If the temperature overheat gage is no longer in the
overheat zone or an overheat warning no longer displays,
the vehicle can be driven. Continue to drive the vehicle
slow for about 10 minutes. Keep a safe vehicle distance
from the car in front of you. If the warning does not come
back on, continue to drive normally.
If the warning continues, pull over, stop, and park the
vehicle right away.
If there is no sign of steam, idle the engine for
three minutes while parked. If the warning is still
displayed, turn off the engine until it cools down.
Also, see “Overheated Engine Protection Operating
Mode” later in this section.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
ENGINE POWER IS REDUCED message is displayed,
an overheat protection mode which alternates ring
groups of cylinders helps prevent engine damage. In this
mode, you will notice a loss in power and engine
performance. This operating mode allows the vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in the
overheat protection mode should be avoided.
5-36