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Test 7: Front Door Switch Circuit

  1. On SL500, go to next step. On CL500, S320, S420 and S500, go to step 3). On SLK230, go to step 4).
  2. Using Harness Adapter (202 589 16 63 00), connect Breakout Box (129 589 00 21 00) to Pneumatic System Equipment (PSE) control module. Measure voltage between positive battery voltage and terminal No. 47 at breakout box. When front doors are closed, less than one volt should exist. Lock vehicle using remote transmitter. Unlock vehicle using remote transmitter. After 40 seconds, battery voltage should exist for .5 seconds. If voltage is as specified, front door switch is okay at this time. If voltage is not as specified, check wiring. See WIRING DIAGRAMS . If wiring is okay, check the following as possible cause and repair as necessary:
    • Perform central locking system TEST 8: DRIVER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform central locking system TEST 9: PASSENGER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 3: CENTRAL LOCKING SYSTEM VACUUM SUPPLY (PASSENGER'S DOOR, REAR DOORS & TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 4: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (PASSENGER'S DOOR, REAR DOORS & TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 6: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 8: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (FUEL DOOR). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
  3. Using Harness Adapter (140 589 13 63 00), connect Breakout Box (129 589 00 21 00) to Pneumatic System Equipment (PSE) control module. Measure voltage between terminals No. 7 and 8 at breakout box. When front doors are closed, less than one volt should exist. Lock vehicle using remote transmitter. Unlock vehicle using remote transmitter. After 40 seconds, battery voltage should exist for .5 seconds. If voltage is as specified, front door switch is okay at this time. If voltage is not as specified, check wiring. See WIRING DIAGRAMS . If wiring is okay, check the following as possible cause and repair as necessary:
    • Perform central locking system TEST 8: DRIVER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform central locking system TEST 9: PASSENGER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 3: CENTRAL LOCKING SYSTEM VACUUM SUPPLY (PASSENGER'S DOOR, REAR DOORS & TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 4: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (PASSENGER'S DOOR, REAR DOORS & TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 6: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 8: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (FUEL DOOR). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
  4. Connect Breakout Box (129 589 00 21 00) to combination control module. Measure voltage between terminals No. 59 and 75 at breakout box. When front doors are closed, less than one volt should exist. Lock vehicle using remote transmitter. Unlock vehicle using remote transmitter. After 40 seconds, battery voltage should exist for .5 seconds. If voltage is as specified, front door switch is okay at this time. If voltage is not as specified, check wiring. See WIRING DIAGRAMS . If wiring is okay, check the following as possible cause and repair as necessary:
    • Perform central locking system TEST 8: DRIVER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform central locking system TEST 9: PASSENGER'S DOOR SWITCH CIRCUIT. See CENTRAL LOCKING under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 2: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (DRIVER'S DOOR). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 4: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (PASSENGER'S DOOR, REAR DOORS & TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 5: CENTRAL LOCKING SYSTEM VACUUM SUPPLY (TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
    • Perform pneumatic system vacuum test TEST 6: CENTRAL LOCKING SYSTEM PRESSURE SUPPLY (TRUNK LID LOCK). See PNEUMATIC SYSTEM EQUIPMENT under SYSTEM TESTS .
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