The skip shift solenoid is a performance 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. |
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.