Hummer 2004 H2 - Manual (Page 108)

If the 4HI or 4HI Lock button is pressed when your
vehicle is in gear and/or moving, the 4HI or 4HI Lock
indicator light will flash for 15 seconds but will not
complete the shift unless your vehicle is moving less
than 2 mph (3.2 km/h) and the transmission is in
NEUTRAL (N).
Notice: Shifting the transmission into gear before
the indicator light stops flashing could cause
damage to the transfer case. Always wait until the
indicator lights stops flashing before putting
the transmission back in gear.
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 4HI.
7. Simultaneously press and hold the 4HI and 4LO
Lock buttons for 10 seconds. The red NEUTRAL
light will come on when the transfer case shift
to NEUTRAL is complete.
8. Turn the ignition to LOCK.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift the transfer case out of NEUTRAL, do the
following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (4HI, 4HI Lock or 4LO Lock).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may start the engine and shift the transmission
to the desired position.
Notice: Shifting the transmission into gear before
the indicator light stops flashing could cause
damage to the transfer case. Always wait until the
indicator lights stops flashing before putting
the transmission back in gear.
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