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Tahoe / Yukon Service Manual

Power Windows Malfunction

Diagnostic Instructions Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Review Strategy Based Diagnosis for an overview of the diagnostic approach. Diagnostic Procedure Instructions provides an overview of each diagnostic category. Diagnostic Fault Information

Circuit Number Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan
1940 B+ U0215 00 U0215 00 — —
3540 B+ U0222 00, U0224 00 U0222 00, U0224 00 — —
4240 B+ U0223 00, U0225 00 U0223 00, U0225 00 — —
6134 Serial Data U0215 00, U0222 00, U0223 00 U0215 00, U0222 00, U0223 00 U0215 00, U0222 00, U0223 00 —
6135 Serial Data U0224 00, U0225 00 U0224 00, U0225 00 U0224 00, U0225 00 —
1184 Signal B1953 11 2 2 —
2763 Signal B1952 11 1 1 —
2764 Signal B1952 11 1 1 —
2765 Signal B1953 11 2 2 —
2766 Signal B1952 11 1 1 —
5295 Signal B1953 11 2 2 —
668 Control 3 3 3 —
669 Control 3 3 3 —
670 Control 4 4 4 —
671 Control 4 4 4 —
Circuit Number Circuit Function Short to Ground Open/High Resistance Short to Voltage Signal Performan
1150 Ground — U0215 00, U0222 00 — —
1250 Ground — 2, 4 — —
1. M74D Front Side Door Window Regulator Motor-Driver = Inoperative 2. M74P Front Side Door Window Regulator Motor-Passenger = Inoperative 3. M74LR Rear Side Door Window Regulator Motor-Left= Inoperative 4. M74RR Rear Side Door Window Regulator Motor-Right= Inoperative

Circuit/System Description The window motors supply 12V signal circuits to their respective window switches, when a window switch has been activated, a switch closes providing a ground to the appropriate signal circuit causing the voltage to drop to 0V. The window motor will detect the voltage drop in the signal circuit and will command the window to move in the desired direction. The driver window control switch also contains control switches for the passenger, left rear and right rear window functions. When a window switch is pressed, a serial data message is sent to the body control module (BCM). The BCM examines the request and checks for messages from other power window motors that may prohibit window movement. If no prohibitive messages have been received, the BCM will send a serial data message to the passenger window motor or to the appropriate rear window motor which will perform the command as requested. Diagnostic Aids The loss of the express up and express down functions for the driver, passenger and rear windows may have occurred for the following reasons: The battery was disconnected The battery was replaced A door wiring harness was disconnected A window motor was disconnected The window motors will need to be normalized in order to restore the express functions, refer to Window Motor Programming - Express Function for the proper procedure. Reference Information Schematic Reference Moveable Window Schematics Connector End View Reference Master Electrical Component List Description and Operation Power Windows Description and Operation Electrical Information Reference Circuit Testing Connector Repairs Testing for Intermittent Conditions and Poor Connections Wiring Repairs Scan Tool Reference Control Module References Circuit/System Verification

  1. Ignition » On / Vehicle » In Service Mode
  2. Operate the component: Driver Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed & Pulled Verify the component works as specified: M74D Front Side Door Window Regulator Motor-Driver= Up M74D Front Side Door Window Regulator Motor-Driver = Express Up M74D Front Side Door Window Regulator Motor-Driver= Down M74D Front Side Door Window Regulator Motor-Driver= Express Down ⇒ If the component does not work as specified Refer to: Circuit/System Testing — Test 1 ⇓ If the component works as specified
  3. Operate the component: S79P Front Side Door Window Switch - Passenger » Pressed & Pulled Verify the component works as specified: M74P Front Side Door Window Regulator Motor-Passenger = Up M74P Front Side Door Window Regulator Motor-Passenger = Express Up M74P Front Side Door Window Regulator Motor-Passenger = Down M74P Front Side Door Window Regulator Motor-Passenger = Express Down ⇒ If the component does not work as specified Refer to: Circuit/System Testing — Test 2 ⇓ If the component works as specified
  4. Operate the component: Window Lockout Switch » Pressed Verify the scan tool parameter: Left Rear Window Lockout Status= Inactive & Active ⇒ If the parameter does not change Replace the component: S79D Front Side Door Window Control Switch-Driver ⇓ If the parameter changes
  5. Window Lockout Switch = Not Activated
  6. Operate the component: S79LR Rear Side Door Window Switch-Left» Pressed & Pulled Verify the component works as specified: M74LR Rear Side Door Window Regulator Motor-Left= Up M74LR Rear Side Door Window Regulator Motor-Left= Down ⇒ If the component does not work as specified Refer to: Circuit/System Testing — Test 3 ⇓ If the component works as specified
  7. Operate the component: Window Lockout Switch » Pressed Verify the scan tool parameter: Right Rear Window Lockout Status= Inactive & Active ⇒ If the parameter does not change Replace the component: S79D Front Side Door Window Control Switch-Driver ⇓ If the parameter changes
  8. Window Lockout Switch = Not Activated
  9. Operate the component: S79RR Rear Side Door Window Switch-Right» Pressed & Pulled Verify the component works as specified: M74RR Rear Side Door Window Regulator Motor-Right= Up M74RR Rear Side Door Window Regulator Motor-Right= Down ⇒ If the component does not work as specified Refer to: Circuit/System Testing — Test 4 ⇓ If the component works as specified
  10. Operate the component: Left Rear Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed & Pulled Verify the component works as specified: M74LR Rear Side Door Window Regulator Motor-Left= Up M74LR Rear Side Door Window Regulator Motor-Left= Down ⇒ If the component does not work as specified Replace the component: S79D Front Side Door Window Control Switch-Driver ⇓ If the component works as specified
  11. Operate the component: Right Rear Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed & Pulled Verify the component works as specified: M74RR Rear Side Door Window Regulator Motor-Right= Up M74RR Rear Side Door Window Regulator Motor-Right= Down ⇒ If the component does not work as specified Replace the component: S79D Front Side Door Window Control Switch-Driver ⇓ If the component works as specified
  12. Operate the component: Passenger Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed & Pulled Verify the component works as specified: M74P Front Side Door Window Regulator Motor-Passenger = Up M74P Front Side Door Window Regulator Motor-Passenger = Express Up M74P Front Side Door Window Regulator Motor-Passenger = Down M74P Front Side Door Window Regulator Motor-Passenger = Express Down ⇒ If the component does not work as specified Replace the component: S79D Front Side Door Window Control Switch-Driver ⇓ If the component works as specified
  13. A fault that is not currently present may have been caused by a intermittent condition. Circuit/System Testing Test 1
  14. Ignition/Vehicle & All vehicle systems » Off
  15. Disconnect the electrical connector: S79D Front Side Door Window Control Switch-Driver
  16. Verify a test lamp illuminates between ground circuit terminal 11 and B+. ⇒ If the test lamp does not illuminate 3.1. Repair the open/high resistance on circuit 1150 or the ground connection. ⇓ If the test lamp illuminates
  17. Ignition » On / Vehicle » In Service Mode
  18. Verify a test lamp Illuminates between B+ circuit terminal 24 and ground. ⇒ If the test lamp does not illuminate and the circuit fuse is good 5.1. Test the B+ circuit 1940 for an open/high resistance. ⇒ if an open/high resistance is found, repair the fault on the circuit. ⇓ If an open or high resistance is not found 5.2. Verify the fuse is not open and there is voltage at the fuse. ⇒ If the test lamp does not illuminate and the circuit fuse is open 5.1. Test the B+ circuit 1940 for a short to ground ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 5.2. Replace the S79D Front Side Door Window Control Switch-Driver ⇓ If the test lamp illuminates
  19. Ignition OFF,Connect the electrical connector. S79D Front Side Door Window Control Switch- Driver
  20. Disconnect the electrical connector: M74D Front Side Door Window Regulator Motor-Driver
  21. Connect a test lamp between the test points: Signal circuit terminal 3 & B+
  22. Ignition » On / Vehicle » In Service Mode
  23. Operate the component: Driver Left Front Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pulled Verify the test lamp state: Driver Left Front Window Switch » Not Used = Test lamp Off Driver Left Front Window Switch » Pulled = Test lamp On ⇒ If the test lamp is always OFF 10.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver 10.2. Test for infinite resistance between the circuit 2763 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 10.3. Test for less than 2 Ω in the circuit 2763 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79D Front Side Door Window Control Switch-Driver ⇒ If the test lamp is always ON 10.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver, ignition ON. 10.2. Test for less than 1 V between the circuit 2763 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79D Front Side Door Window Control Switch-Driver ⇓ If the test lamp turns ON and OFF
  24. Connect a test lamp between the test points: Signal circuit terminal 7 & B+
  25. Ignition » On / Vehicle » In Service Mode
  26. Operate the component: Driver Left Front Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed Verify the test lamp state: Driver Left Front Window Switch » Not Used = Test lamp Off Driver Left Front Window Switch » Pressed = Test lamp On ⇒ If the test lamp is always OFF 13.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver 13.2. Test for infinite resistance between the circuit 2764 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 13.3. Test for less than 2 Ω in the circuit 2764 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79D Front Side Door Window Control Switch-Driver ⇒ If the test lamp is always ON 13.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver, ignition ON. 13.2. Test for less than 1 V between the circuit 2764 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79D Front Side Door Window Control Switch-Driver. ⇓ If the test lamp turns ON and OFF
  27. Connect a test lamp between the test points: Signal circuit terminal 5 & B+
  28. Ignition » On / Vehicle » In Service Mode
  29. Operate the component: Driver Left Front Window Switch @ S79D Front Side Door Window Control Switch-Driver» Pressed & Pulled Verify the test lamp state: Driver Left Front Window Switch » Not Used = Test lamp Off Driver Left Front Window Switch » Pressed = Test lamp On Driver Left Front Window Switch » Pulled = Test lamp On ⇒ If the test lamp is always OFF 16.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver 16.2. Test for infinite resistance between the circuit 2766 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 16.3. Test for less than 2 Ω in the circuit 2766 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79D Front Side Door Window Control Switch-Driver ⇒ If the test lamp is always ON 16.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79D Front Side Door Window Control Switch-Driver, ignition ON. 16.2. Test for less than 1 V between the circuit 2766 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79D Front Side Door Window Control Switch-Driver. ⇓ If the test lamp turns ON and OFF
  30. Test or replace the component: M74D Front Side Door Window Regulator Motor-Driver Test 2
  31. Ignition/Vehicle & All vehicle systems » Off
  32. Disconnect the electrical connector: S79P Front Side Door Window Switch - Passenger
  33. Verify a test lamp illuminates between ground circuit terminal 1 and B+. ⇒ If the test lamp does not illuminate 3.1. Repair the open/high resistance on circuit 1250 or the ground connection. ⇓ If the test lamp illuminates
  34. Connect the electrical connector. S79P Front Side Door Window Switch - Passenger
  35. Disconnect the electrical connector: M74P Front Side Door Window Regulator Motor-Passenger
  36. Connect a test lamp between the test points: Signal circuit terminal 3 & B+
  37. Ignition » On / Vehicle » In Service Mode
  38. Operate the component: S79P Front Side Door Window Switch - Passenger » Pulled Verify the test lamp state: S79P Front Side Door Window Switch - Passenger » Not Used = Test lamp Off S79P Front Side Door Window Switch - Passenger » Pulled = Test lamp On ⇒ If the test lamp is always OFF 8.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger 8.2. Test for infinite resistance between the circuit 1184 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 8.3. Test for less than 2 Ω in the circuit 1184 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79P Front Side Door Window Switch-Passenger ⇒ If the test lamp is always ON 8.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger ignition ON. 8.2. Test for less than 1 V between the circuit 1184 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79P Front Side Door Window Switch-Passenger ⇓ If the test lamp turns ON and OFF
  39. Connect a test lamp between the test points: Signal circuit terminal 7 & B+
  40. Ignition » On / Vehicle » In Service Mode
  41. Operate the component: S79P Front Side Door Window Switch - Passenger » Pressed Verify the test lamp state: S79P Front Side Door Window Switch - Passenger » Not Used = Test lamp Off S79P Front Side Door Window Switch - Passenger » Pressed = Test lamp On ⇒ If the test lamp is always OFF 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger 11.2. Test for infinite resistance between the circuit 5295 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 11.3. Test for less than 2 Ω in the circuit 5295 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79P Front Side Door Window Switch-Passenger ⇒ If the test lamp is always ON 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger, ignition ON. 11.2. Test for less than 1 V between the circuit 5295 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79P Front Side Door Window Switch-Passenger. ⇓ If the test lamp turns ON and OFF
  42. Connect a test lamp between the test points: Signal circuit terminal 5 & B+
  43. Ignition » On / Vehicle » In Service Mode
  44. Operate the component: S79P Front Side Door Window Switch - Passenger » Pressed & Pulled Verify the test lamp state: S79P Front Side Door Window Switch - Passenger » Not Used = Test lamp Off S79P Front Side Door Window Switch - Passenger » Pressed = Test lamp On S79P Front Side Door Window Switch - Passenger » Pulled = Test lamp On ⇒ If the test lamp is always OFF 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger 14.2. Test for infinite resistance between the circuit 2765 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 14.3. Test for less than 2 Ω in the circuit 2765 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79P Front Side Door Window Switch-Passenger ⇒ If the test lamp is always ON 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79P Front Side Door Window Switch-Passenger, ignition ON. 14.2. Test for less than 1 V between the circuit 2765 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79P Front Side Door Window Switch-Passenger. ⇓ If the test lamp turns ON and OFF
  45. Test or replace the component: M74P Front Side Door Window Regulator Motor-Passenger Test 3
  46. Ignition/Vehicle & All vehicle systems » Off
  47. Disconnect the electrical connector: S79LR Rear Side Door Window Switch - Left
  48. Verify a test lamp illuminates between ground circuit terminal 7 and B+. ⇒ If the test lamp does not illuminate 3.1. Repair the open/high resistance on circuit 1150 or the ground connection. ⇓ If the test lamp illuminates
  49. Ignition » On / Vehicle » In Service Mode
  50. Verify a test lamp Illuminates between B+ circuit terminal 8 and ground. ⇒ If the test lamp does not illuminate and the circuit fuse is good 5.1. Test the B+ circuit 3540 for an open/high resistance. ⇒ if an open/high resistance is found, repair the fault on the circuit. ⇓ If an open or high resistance is not found 5.2. Verify the fuse is not open and there is voltage at the fuse. ⇒ If the test lamp does not illuminate and the circuit fuse is open 5.1. Test the B+ circuit 3540 for a short to ground ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 5.2. Replace the S79LR Rear Side Door Window Switch - Left ⇓ If the test lamp illuminates
  51. Ignition/Vehicle » Off
  52. Connect the electrical connector. S79LR Rear Side Door Window Switch - Left
  53. Disconnect the electrical connector: M74LR Rear Side Door Window Regulator Motor - Left
  54. Connect a test lamp between the test points: Control circuit terminal 1 & Ground
  55. Ignition » On / Vehicle » In Service Mode
  56. Operate the component: S79LR Rear Side Door Window Switch - Left Pulled Verify the test lamp state: S79LR Rear Side Door Window Switch - Left » Not Used = Test lamp Off S79LR Rear Side Door Window Switch - Left » Pulled = Test lamp On ⇒ If the test lamp is always OFF 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79LR Rear Side Door Window Switch - Left 11.2. Test for infinite resistance between the circuit 668 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 11.3. Test for less than 2 Ω in the circuit 668 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79LR Rear Side Door Window Switch - Left ⇒ If the test lamp is always ON 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79LR Rear Side Door Window Switch - Left ignition ON. 11.2. Test for less than 1 V between the circuit 668 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79LR Rear Side Door Window Switch - Left ⇓ If the test lamp turns ON and OFF
  57. Connect a test lamp between the test points: Control circuit terminal 2 & Ground
  58. Ignition » On / Vehicle » In Service Mode
  59. Operate the component: S79LR Rear Side Door Window Switch - Left Pulled Verify the test lamp state: S79LR Rear Side Door Window Switch - Left » Not Used = Test lamp Off S79LR Rear Side Door Window Switch - Left » Pressed = Test lamp On ⇒ If the test lamp is always OFF 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79LR Rear Side Door Window Switch - Left 14.2. Test for infinite resistance between the circuit 669 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 14.3. Test for less than 2 Ω in the circuit 669 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79LR Rear Side Door Window Switch - Left ⇒ If the test lamp is always ON 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79LR Rear Side Door Window Switch - Left ignition ON. 14.2. Test for less than 1 V between the circuit 669 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79LR Rear Side Door Window Switch - Left ⇓ If the test lamp turns ON and OFF
  60. Test or replace the component: M74LR Rear Side Door Window Regulator Motor - Left Test 4
  61. Ignition/Vehicle & All vehicle systems » Off
  62. Disconnect the electrical connector: S79RR Rear Side Door Window Switch - Right
  63. Verify a test lamp illuminates between ground circuit terminal 7 and B+. ⇒ If the test lamp does not illuminate 3.1. Repair the open/high resistance on circuit 1250 or the ground connection. ⇓ If the test lamp illuminates
  64. Ignition » On / Vehicle » In Service Mode
  65. Verify a test lamp Illuminates between B+ circuit terminal 8 and ground. ⇒ If the test lamp does not illuminate and the circuit fuse is good 5.1. Test the B+ circuit 4240 for an open/high resistance. ⇒ if an open/high resistance is found, repair the fault on the circuit. ⇓ If an open or high resistance is not found 5.2. Verify the fuse is not open and there is voltage at the fuse. ⇒ If the test lamp does not illuminate and the circuit fuse is open 5.1. Test the B+ circuit 4240 for a short to ground ⇒ If a short to ground is found, repair the fault on the circuit. ⇓ If a short to ground is not found 5.2. Replace the S79RR Rear Side Door Window Switch - Right ⇓ If the test lamp illuminates
  66. Connect the electrical connector. S79RR Rear Side Door Window Switch - Right
  67. Disconnect the electrical connector: M74RR Rear Side Door Window Regulator Motor - Right
  68. Connect a test lamp between the test points: Control circuit terminal 1 & Ground
  69. Ignition » On / Vehicle » In Service Mode
  70. Operate the component: S79RR Rear Side Door Window Switch - Right Pulled Verify the test lamp state: S79RR Rear Side Door Window Switch - Right » Not Used = Test lamp Off S79RR Rear Side Door Window Switch - Right » Pulled = Test lamp On ⇒ If the test lamp is always OFF 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79RR Rear Side Door Window Switch - Right 11.2. Test for infinite resistance between the circuit 670 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 11.3. Test for less than 2 Ω in the circuit 670 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79RR Rear Side Door Window Switch - Right ⇒ If the test lamp is always ON 11.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79RR Rear Side Door Window Switch - Right ignition ON. 11.2. Test for less than 1 V between the circuit 670 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79RR Rear Side Door Window Switch - Right ⇓ If the test lamp turns ON and OFF
  71. Connect a test lamp between the test points: Control circuit terminal 2 & Ground
  72. Ignition » On / Vehicle » In Service Mode
  73. Operate the component: S79RR Rear Side Door Window Switch - Right Pulled Verify the test lamp state: S79RR Rear Side Door Window Switch - Right » Not Used = Test lamp Off S79RR Rear Side Door Window Switch - Right » Pressed = Test lamp On ⇒ If the test lamp is always OFF 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79RR Rear Side Door Window Switch - Right 14.2. Test for infinite resistance between the circuit 671 and ground. ⇒ If less than infinite resistance, repair the short to ground on the circuit. ⇓ If infinite resistance 14.3. Test for less than 2 Ω in the circuit 671 end to end. ⇒ If 2 Ω or greater, repair the open/high resistance in the circuit. ⇒ If less than 2 Ω, replace the S79RR Rear Side Door Window Switch - Right ⇒ If the test lamp is always ON 14.1. Ignition OFF, remove the test lamp, disconnect the harness connector at the S79RR Rear Side Door Window Switch - Right ignition ON. 14.2. Test for less than 1 V between the circuit 671 and ground. ⇒ If 1 V or greater, repair the short to voltage on the circuit. ⇒ If less than 1 V, replace the S79RR Rear Side Door Window Switch - Right ⇓ If the test lamp turns ON and OFF
  74. Test or replace the component: M74RR Rear Side Door Window Regulator Motor - Right Component Testing M74LR Rear Side Door Window Regulator Motor - Left / M74RR Rear Side Door Window Regulator Motor - Right
  75. Ignition/Vehicle » Off
  76. Disconnect the appropriate electrical connector: M74LR Rear Side Door Window Regulator Motor - Left or M74RR Rear Side Door Window Regulator Motor - Right
  77. Connect a 25 A fused jumper wire between the test points: Control terminal 1 & B+
  1. Momentarily connect a jumper wire between the test points: Control terminal 2 & Ground Reverse the jumper wires 2 times between the terminals. Verify the component works as specified: M74 Window Motor = Up & Down ⇒ If not the specified state Replace the component: M74LR Rear Side Door Window Regulator Motor - Left or M74RR Rear Side Door Window Regulator Motor - Right ⇓ If the specified state
  2. All OK. Repair Instructions Perform the Diagnostic Repair Verification after completing the repair: Diagnostic Repair Verification Rear Side Door Window Switch Replacement Front Side Door Window Control Switch Replacement Front Side Door Window Switch Replacement - Right Side Front Side Door Window Regulator Motor Replacement Rear Side Door Window Regulator Motor Replacement