Sierra 3500 4WD V8-6.6L DSL Turbo VIN 2 (2004)
Glow Plug: Description and Operation
GLOW PLUGS
The glow plugs are 4.7.volt heaters in each of the cylinders that turn ON, then pulse-width modulated when the ignition switch is turned to the RUN
position prior to starting the engine. They remain pulsing a short time after starting, then they are turned OFF.
A Wait to Start lamp on the instrument panel provides information on engine starting conditions. The Wait to Start lamp will not illuminate during
post-start glow plug operation.