GMC 2003 Sierra - Manual (Page 413)

If No Steam Is Coming From Your
Engine
An ovBT+ieal warning, afung wilh a low coolant message,
can jndioaie a serjous problafn. For nwre informaHon,
saa
Driver !riiortr)allOf} Center {DiC} on page J-50.
If ^ou gel an engine ouertTflal warning wilh no
low coolant massage, but see or hear no steam, the
probfam may not be too serious. Somelimas the engine
can get a little loo hot when you:
• CHmb a long hill on a hot day,
* Slop after high speed driving.
♦ Idle for long periods in traffic.
* Tow a trailer See ^Driving on Grades"* undar
Towfng a TraHer on page 4-&G.
If you gel ihe overheal warning with no sign of steam,
try thfs for a mmute or so:
1. If you have an air conditioner and it's on, turn it off.
2. Turm on your heater to full hat at Ibe highest fan
speed and open tha window as necessary.
3. If you're in a traffic jam, shift to NEUTRAL fN);
otherwise, shift lo Ihe highesl gear while
driving - AUTOMATIC OVERDRIVE ® or
DRIVE (D) lor automatic transmissions.
If you no longer have ihe overheal warning, you can
drive. Just to be safe, drive slower for about if) minutes-.
If lha warning doesn't come back on, you can drive
normally.
If the warning continues, poll over, stop, and park your
vehiqla right away.
If there's slill no sign ol steam, push down the
acceleratar until tho engine speed is about twice as fast
as normal Idle speed for al leasi three minutes while
you're parked. II you still have the warning,
turn aft rhg
engine and get evetyene cut of ihe vehicia unhl it
cools down. Also, see ‘'Overtiealed Engine Protection
Operating Mode" listed praviausly in this section.
You may decide not lo lifl The hood but to gel service
help right away.
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