The high-line or premium version of the CTM must have the VTSS function electronically enabled in order for the VTSS to perform as designed. The logic in the CTM keeps its VTSS function dormant until it is enabled using a DRBIII® scan tool. The VTSS function of the high-line or premium CTM is enabled on vehicles equipped with the VTSS option at the factory, but a service replacement CTM must be VTSS-enabled by the dealer using a DRBIII® scan tool. Refer to the appropriate diagnostic information.
The VTSS engine no-run feature is disabled when it is shipped from the factory. This is done by programming within the Powertrain Control Module (PCM). The logic in the PCM prevents the VTSS engine no-run feature from arming until the engine start counter within the PCM sees twenty engine starts. The VTSS no-run feature must be enabled by the dealer when the vehicle is received from the assembly plant. Once the VTSS engine no-run feature has been enabled, it cannot be disabled unless the PCM is replaced with a new unit. The same VTSS engine no-run feature enable logic will apply anytime the PCM is replaced with a new unit.