Operation CHARM: Car repair manuals for everyone.

Door Locks: Description and Operation

2-DOOR, EXTENDED CAB AND UTILITY

When a Door Lock Switch is operated, both of the doors will lock or unlock. Each lock can also be operated manually. The locks are operated by reversible motors that receive voltage from the ACC-BATT Circuit Breaker. The Door Lock Switches operate to turn the Motors on by supplying battery voltage to one of the terminals and ground the other terminal.

When either Door Lock Switch is moved to the LOCK position, it completes the circuit to the Motors. Voltage is supplied to the GRA (295) wire and to the Door Lock Motors, which are grounded by the TAN (294) wire from the other terminal of the Motor through the other switch contact to ground. The Motor in each door runs to operate the Door Locks. When the Door Lock Switch is released, the circuit is opened and the Motors turn off.

A similar action occurs with either of the Door Lock Switches closing to the UNLOCK position. Now the TAN (294) wires to the Motors supply battery voltage and the GRA (295) wires are grounded. The polarity of the voltage to the Motors has reversed. The Motors run in the opposite direction to unlock the doors.

The Door Lock Switches are usually closed for just a moment. If the Door Lock Switches are held closed, a circuit breaker in each Motor will open to protect against damage. The circuit breakers close automatically when they cool off.

CREW CAB AND SUBURBAN

When a Door Lock Switch is operated, all of the doors will lock or unlock. Each lock can also be operated manually. The locks are operated by reversible motors that receive voltage from the ACC-BATT Circuit Breaker. The Door Lock Switches operate to turn the Motors on by supplying battery voltage to one of the terminals and ground the other terminal.

When either Door Lock Switch is moved to the LOCK position, it completes the circuit to the Motors. Voltage is supplied to the GRA (295) wire and to the Door Lock Motors, which are grounded by the TAN (294) wire from the other terminal of the Motor through the other switch contact and through the Door Lock Relay to the BLK (150) wire and ground G202. The Motor in each door runs to operate the Door Locks. When the Door Lock Switch is released, the circuit is opened and the Motors turn off.

POWER DOOR LOCKS

A similar action occurs with either of the Door Lock Switches closing to the UNLOCK position. Now the TAN (294) wires to the Motors supply battery voltage and the GRA (295) wires are grounded. The polarity of the voltage to the Motors has reversed. The Motors run in the opposite direction to unlock the doors.

The Door Lock Switches are usually closed for just a moment. If the Door Lock Switches are held closed, a circuit breaker in each Motor will open to protect against damage. The circuit breakers close automatically when they cool off.

REAR CARGO DOORS (SUBURBAN)

The Rear Cargo Doors must be fully closed for the Door Lock Motor to operate. The Door Lock Motor is located in the right rear cargo door. Contact buttons are located on the cargo door opening on the body and also on the right rear cargo door.