GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 335
3. Connect the vehicle to abattery charger.
4. Turn the ignition on for Key Access vehicles or to Service
Only for Keyless Access
vehicles. See Ignition Positions
(Key Access) 0220 or
Ignition Positions (Keyless
Access) 0222.
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator and the brake for
automatic transmission
vehicles for two seconds, then
release.
At the end of the cycle, check the
coolant level in the surge tank and
add coolant if it is low. Turn off the
vehicle, allow the Electronic Control
Module (ECM) to go to sleep, about
2 minutes, and repeat Steps 3-7.
Listen for pump activation and
movement of the control valves
while watching the level of the
coolant in the surge tank. If the tank
empties, turn the ignition off, carefully remove the surge tank cap,
refill to the indicated mark, and
repeat Steps 3-6. The fill and air
removal process will run for
approximately 10 minutes.
How to Add Coolant to the
Coolant Surge Tank for
Gasoline Engines Except L3B
If the vehicle has a diesel engine,
see
“Cooling System” in the
Duramax diesel supplement for the
proper coolant fill procedure.
{Warning
Spilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough.
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
