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Makes 🢒 GMC_Truck 🢒 2002 🢒 GMC C Sierra - 2WD 🢒 Body and Accessories 🢒 Seats 🢒 Power Seat Does Not Tilt Rearward

Power Seat Does Not Tilt Rearward with Memory

Step

Action

Values

Yes

No

Schematic Reference: Memory Seats Schematics

Important: This table assumes that all mechanical linkage and drivers are free from obstruction and not binding.

1

Did you review the power seats system Description and Operation and perform the necessary inspections?

--

Go to Step 2

Go to Symptoms - Seats

2

Verify the fault is present.

Does the system operate normally?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Does the rear vertical adjuster motor operate for approximately 1 revolution and stop?

--

Go to Step 4

Go to Step 7

4
  1. Disconnect the rear vertical motor position sensor connector.
  2. Connect a DMM from the 5-volt reference circuit terminal in the position sensor harness connector to a good ground.
  3. Activate a seat adjuster switch.

Is the voltage at or near the specified value?

5 V

Go to Step 5

Go to Step 13

5
  1. Connect a DMM from the signal circuit terminal in the position sensor harness connector to a good ground.
  2. Activate a seat adjuster switch.

Is the voltage at or near the specified value?

5 V

Go to Step 6

Go to Step 14

6
  1. Connect a DMM from the 5-volt reference circuit terminal to the low reference circuit terminal in the position sensor harness connector.
  2. Activate a seat adjuster switch.

Is the voltage at or near the specified value?

5 V

Go to Step 18

Go to Step 15

7
  1. Disconnect the memory seat module connector C3.
  2. Connect a test lamp from the rear vertical up switch signal circuit terminal in the harness connector to a good ground.
  3. Press the rear vertical up switch.

Does the test lamp illuminate?

--

Go to Step 8

Go to Step 10

8
  1. Connect a test lamp from the rear vertical down switch signal circuit terminal in the harness connector to a good ground.
  2. Press the rear vertical down switch.

Does the test lamp illuminate?

--

Go to Step 9

Go to Step 11

9
  1. Connect the memory seat module connector C3.
  2. Disconnect the rear vertical motor control circuit connector.
  3. Connect a test lamp between the rear vertical motor control circuit terminals in the harness connector.
  4. Operate the rear vertical adjuster switch in both directions.

Does the test lamp illuminate when the switch is activated in both directions?

--

Go to Step 17

Go to Step 12

10

Test the rear vertical up switch signal circuit for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 16

11

Test the rear vertical down switch signal circuit for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 16

12

Test the rear vertical motor control circuits for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 19

13

Test the rear vertical motor position sensor 5-volt reference circuit for the following conditions:

    • Open
    • Short to ground
    • Short to voltage

Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 19

14

Test the rear vertical motor position sensor signal circuit for the following conditions:

    • Open
    • Short to ground
    • Short to voltage

Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 19

15

Test rear vertical motor position sensor low reference circuit for an open or short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 19

16

Inspect for poor connections at the power seat switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 20

17

Inspect for poor connections at the rear vertical motor control circuit connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 21

18

Inspect for poor connections at the rear vertical motor position sensor connector. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 21

19

Inspect for poor connections at the memory seat module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 23

Go to Step 22

20

Replace the power seat switch assembly. Refer to Power Seat Switch Replacement .

Did you complete the replacement?

--

Go to Step 23

--

21

Replace the rear vertical adjuster motor. Refer to Front Seat Adjuster Motor Replacement .

Did you complete the replacement?

--

Go to Step 23

--

22

Replace the memory seat module. Refer to Memory Seat Control Module Replacement .

Did you complete the replacement?

--

Go to Step 23

--

23

Operate the system to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Power Seat Does Not Tilt Rearward w/o Memory

Step

Action

Yes

No

Schematic Reference: Power Seats Schematics

Important: This table assumes that all mechanical linkage and drivers are free from obstruction and not binding.

1

Did you review the Power Seats System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Seats

2

Operate the power seat in all directions.

Does the system operate normally?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3
  1. Disconnect the rear vertical motor connector.
  2. Connect a test lamp between the rear vertical motor control circuit terminals in the harness connector.
  3. Operate the rear vertical adjuster switch in both directions.

Does the test lamp illuminate when the switch is activated in both directions?

Go to Step 6

Go to Step 4

4

Test the rear vertical motor control circuits for an open or short to ground. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Inspect the poor connections at the harness connector of the power seat switch. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

6

Inspect the poor connections at the harness connector of the rear vertical motor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

Replace the rear vertical adjuster motor. Refer to Front Seat Adjuster Motor Replacement .

Did you complete the replacement?

Go to Step 9

--

8

Replace the power seat switch. Refer to Power Seat Switch Replacement .

Did you compete the replacement?

Go to Step 9

--

9

Operate the system to verify the repair.

Did you correct the condition?

System OK

Go to Step 2