General Description

ANTI-LOCKOUT FEATURE DESCRIPTION
The Anti-Lockout feature is designed to prevent locking the vehicle doors while the ignition key is in the ignition switch

With the ignition key in the ignition switch the Key-In Warning switch is closed. Since the Key-In Warning switch is connected to G200 through CKT150 (BLK) and to the BCM through CKT80 (LT GRN), the reference voltage is pulled low. This causes two functions to occur:
^ Key-In Warning Chime is turned ON (if the drivers door is opened).
^ The BCM's solid state logic prevents the doors from being locked.

DOOR DESCRIPTION
Doors on C/K model trucks use hinges that are welded to the door and to the body. There is no adjustment to this type of hinge. The replacement hinges bolt to the door and to the body side pillar. The replacement hinges are adjustable.

POWER WINDOWS OPERATION
A permanent magnet motor operates each of the power side windows. Each motor raises or lowers the glass when the motor receives voltage. The direction the motor turns depends on the polarity of the supply voltage. The side window switches control the polarity of the supply voltage.

The left front door lock and side window switch controls all of the motors. The other window switches control only the window regulator motor in that door.

A built-in circuit breaker protects each motor. The circuit breaker opens the circuit when the switch is open for too long of a period of time under the following conditions:
^ The window has an obstruction.
^ The window is fully open or fully closed.

The circuit breaker resets automatically as the circuit breaker cools.

MASTER WINDOW SWITCH OPERATION
When the ignition switch is in the RUN position, battery voltage is available through the PWR WDO circuit breaker and CKT 343 (YEL) to the left front door lock and side window switch. The operation of the left front wind up switch supplies battery voltage to the left front window regulator motor through CKT 164 (DK BLU). The window motor grounds through CKT 165 (BRN) and through the window switch down contact.

The regulator motor runs in order to drive upward the window. The operation of the down switch supplies battery voltage in the opposite direction to the window regulator motor through CKT 165 (BRN). The window regulator grounds through CKT 164 (DK BLU) and the window switch up contact. The motor runs in order to drive downward the window.

INDIVIDUAL WINDOW SWITCH OPERATION
When the ignition switch is in the RUN position, battery voltage is available to the right front door lock and side window switch through the PWR WDO circuit breaker and through CKT 343 (YEL) to terminal F. The operation of the up switch in the right front window switch supplies battery voltage to the right front window regulator motor through CKT 666 (DK BLU). The motor grounds through CKT 667 (BRN), the down contact in the window switch, CKT 167 (TAN), and the down contact in the left front door lock and side window switch. The motor runs in order to drive upward the window. The operation of the down switch in the window switch supplies battery voltage in opposite direction to the window regulator motor through CKT 667 (BRN). The motor grounds through CKT 66 (DK BLU), the up contact in the window switch, CKT 166 (LT BLU), and the up contact in the left front door lock and side window switch. The motor runs in order to drive downward the window.