Test 4: Interior Central Locking Switch (SL500)

Turn ignition switch to LOCK position. Disconnect Pneumatic System Equipment (PSE) control module. Using Harness Adapter (202 589 16 63 00), connect Breakout Box (129 589 00 21 00) to PSE control module harness connectors. Measure resistance between ground and terminal No. 49 at breakout box. When interior central locking switch is open, greater than 20 k/ohms should exist. When interior central locking switch is closed, less than one ohm should exist. If resistance is as specified, interior central locking switch is okay at this time. If resistance is not as specified, check wiring. See WIRING DIAGRAMS . If wiring is okay, suspect faulty interior central locking switch.