[GOLDCYLON]

Originally Posted by Paul Workman

(...or is that "UP SHIFT")

Is the light triggered simply at a fixed rpm, or dependant on variable demand conditions?

TIA,

P.

Paul the short answer is Yes. The longer answer is listed below with all the factors for CAGS or Skip Shift from GM

Gear Select - Skip Shift (CAGS)
To ensure good fuel economy and compliance with federal economy standards, SECOND and THIRD gear are inhibited when shifting out of FIRST gear, under the following conditions:

Coolant temperature is above 50°C (122°F)
Corvette speed is 20 - 29 km/h (12 - 19 mph)
Throttle is opened 35 percent or less

Skip Shift Description and Operation
The skip shift solenoid is a Peformance feature which forces the driver to shift from first gear to fourth gear during light acceleration and low engine load conditions. This feature is used to ensure good fuel economy and compliance with federal economy standards. The skip shift system consist of the following components:

· The powertrain control module (PCM) .
· The skip shift solenoid.

· The skip shift lamp. With the ignition ON, battery voltage is supplied directly to the skip shift solenoid. The powertrain control module (PCM) controls the solenoid by grounding the control circuit. When the skip shift system is active the PCM also grounds the control circuit of the skip shift lamp. The lamp illuminates to inform the driver that the 1-4 skip shift is engaged. The PCM determines when the skip shift system is active when the following parameters are met:

· The vehicle speed is between 24 - 31 km/h (15 - 19 mph) .

· The engine coolant temperature (ECT) is greater than 77°C (171°F) .

· The BARO is greater than 76 kPa.

· The accelerator pedal position (APP) is less than 26 percent. When the conditions are met the powertrain control module (PCM) grounds the skip shift solenoid control circuit. This energizes the skip shift solenoid and mechanically blocks the gear shift lever from going into the second or third gear positions. When the drivers pulls back on the shift lever with the system enabled the transmission will go into fourth gear.

When the conditions for skip shift engagement are no longer met the powertrain control module (PCM) disables the skip shift solenoid, allowing the driver to use second and third gears.
Once the skip shift solenoid is enabled the system will not be re-enabled until the vehicle speed returns to 0 km/h (0 mph) and the conditions for enabling skip shift solenoid are met.


GC