2000 Cadillac DeVille Brake Switch Circuit Low Input

Download . Circuit Description The torque converter clutch (TCC) brake switch is used to indicate the status of the brake pedal (applied or released). If the PCM detects an open TCC brake switch (stuck ON) during accelerations, then DTC P0719 sets. DTC P0719 is a type C DTC. Conditions for Running the DTC * No VSS DTCs P0502 or P0503. * DTC P0719 has not passed this ignition cycle. Conditions for Setting the DTC The TCC brake switch input is at 0 volts for 15 minutes and the following conditions occur 8 times without a status change on the TCC brake input: * The vehicle speed is less than 8 km/h (5 mph). * The vehicle accelerates to 32 km/h (20 mph) within 2-6 seconds. * Then the vehicle speed remains above 32 km/h (20 mph) for 6 seconds. Action Taken When the DTC Sets * The PCM does not illuminate the malfunction indicator lamp (MIL). * SERVICE ELECTRICAL SYSTEM displays on the driver information center (DIC). * The PCM uses throttle angle and vehicle speed for TCC control. * The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records. * The PCM stores DTC P0719 in PCM history. Conditions for Clearing the DIC/DTC * The PCM clears the DIC message when the condition no longer exists. * The TCC brake switch input must indicate ignition voltage for 2 seconds. * A scan tool can clear the DTC. * The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring. * The PCM cancels the DTC default actions when the fault no longer exists and/or the ignition switch is OFF long enough in order to power down the PCM. Diagnostic Aids * If the PCM detects a TCC brake switch circuit fault, then the TCC brake switch input is disregarded for TCC scheduling. The PCM then uses throttle position and vehicle speed inputs to determine TCC application and release. Use of these inputs may result in a noticeable harsh apply or abrupt release of the TCC. * Inspect the TCC brake switch for proper adjustment. * Inspect the connectors at the PCM, the TCC brake switch and all other circuit connecting points for an intermittent condition. Refer to Testing for Intermittent and Poor Connections in Wiring Systems. * Inspect the circuit wiring for an intermittent condition. Refer to Testing for Electrical Intermittents in Wiring Systems. Test Description