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HOMESERVICE MANUALSGMC1999FORWARD CONTROL 5.7 R, AUTOMATICREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 743 (SEAT SYSTEM)DIAGNOSTIC INFORMATION AND PROCEDURESPOWER SEAT INOPERATIVE (WITH MEMORY)
1999 GMC Forward Control 5.7 R, Automatic

Power Seat Inoperative (with Memory)

1999 GMC Forward Control 5.7 R, AutomaticSECTION Power Seat Inoperative (with Memory)
WARNING: This page is about a different car, the 2004 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
Power Seat Inoperative (with Memory)

Step Action Yes No
Schematic Reference:  Memory Seats Schematics  
DEFINITION: One or more of the memory seat adjustments are inoperative and no DTCs are set.
1 Did you perform the Power Seat Systems Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Power Seat Systems 
2 Attempt to operate all of the memory seat adjustments through the full range.
Do all of the memory seat functions operate normal?		 Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3
  1. Install a scan tool.
  2. Observe the status of the inoperative seat adjuster switch.
  3. Press the inoperative seat adjuster switch.
Does the scan tool indicate the switch status is active?		 Go to Step 6  Go to Step 4 
4
  1. Disconnect the seat adjuster switch connector.
  2. Connect a fused jumper wire from the adjuster switch low reference circuit terminal to the inoperative switch signal circuit terminal in the harness connector.
Does the scan tool indicate the switch status is active?		 Go to Step 8  Go to Step 5 
5 Test and repair the adjuster switch low reference circuit and the inoperative switch signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs or Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 11  Go to Step 10 
6
  1. Disconnect the seat adjuster motor assembly connector.
  2. Connect a test lamp across the inoperative adjuster motor control circuit terminals in the harness connector.
  3. Press the inoperative seat adjuster switch.
Does the test lamp illuminate?		 Go to Step 9  Go to Step 7 
7 Test and repair the inoperative seat adjuster motor control circuits for an open, high resistance, or short to ground. Refer to Circuit Testing and Wiring Repairs or Connector Repairs in Wiring Systems.
Did you find and correct the condition?		 Go to Step 11  Go to Step 10 
8 Replace the seat adjuster switch. Refer to Seat Switch Replacement - Power .
Is the repair complete?		 Go to Step 11  -
9 Replace the inoperative seat adjuster motor. Refer to Seat Adjuster Motor Replacement - Front .
Is the repair complete?		 Go to Step 11  -
10 Replace the memory seat module. Refer to Memory Seat Control Module Replacement .
Is the repair complete?		 Go to Step 11  -
11 Operate the system in order to verify the repair.
Did you correct the condition?		 System OK Go to Step 3 
RENDER: 1.0x

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