GM Service Manual Online
For 1990-2009 cars only

Power Seat Does Not Tilt Rearward (LH and RH)

Step

Action

Value(s)

Yes

No

DEFINITION: Upward or downward controls are inoperative for the rear vertical motor. Horizontal and front tilt motors operate normally. Either driver's side or passenger's side seat.

1

Were you sent here from the Power Seat System Diagnostic System Check?

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Go to Step 2

Go to Power Seat System Diagnostic System Check

2

  1. Disconnect the LH or RH seat adjuster switch connector.
  2. Connect a jumper wire from:
  3. •  LEFT SIDE = The seat adjuster switch connector terminal 24 to ground.
    • RIGHT SIDE = The seat adjuster switch connector terminal 3 to ground.

Does the seat motor move?

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Go to Step 3

Go to Step 5

3

Connect the jumper wire from:

    • LEFT SIDE = The seat adjuster switch connector terminal 3 to ground.
    • RIGHT SIDE = The seat adjuster switch connector terminal 24 to ground.

Does the seat motor move?

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Go to Step 4

Go to Step 7

4

Replace the RH or LH seat adjuster switch.

Is the repair complete?

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Go to Power Seat System Diagnostic System Check

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5

  1. Disconnect the RH or LH seat relay center connector C1.
  2. Use a DMM to measure CKT 1521 for continuity between the seat relay center connector C1 terminal 12 and the seat adjuster switch connector:
  3. • LEFT SIDE = Terminal 24.
    • RIGHT SIDE = Terminal 3.

Is CKT 1521 continuous between these two connectors?

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Go to Step 9

Go to Step 6

6

Locate and repair an open or a high resistance in CKT 1521.

Is the repair complete?

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Go to Power Seat System Diagnostic System Check

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7

  1. Disconnect the RH or LH seat relay center connector C1.
  2. Use a DMM to measure CKT 1519 for continuity between the seat relay center connector C1 terminal 1 and the seat adjuster switch connector:
  3. • LEFT SIDE = Terminal 3.
    • RIGHT SIDE = Terminal 24.

Is CKT 1519 continuous between these two connectors?

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Go to Step 9

Go to Step 8

8

Locate and repair an open or a high resistance in CKT 1519.

Is the repair complete?

--

Go to Power Seat System Diagnostic System Check

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9

  1. Disconnect the RH or LH seat relay center connector C2 and C3.
  2. Using two jumper wires, perform the following test:
  3. • Connect a jumper wire between battery power and the seat relay center connector C2 terminal F.
    • Connect a second jumper wire between ground and the seat relay center connector C3 terminal D.
  4. Now reverse the jumper wires as follows:
  5. • Connect the jumper wire between battery power and the seat relay center connector C3 terminal D.
    • Connect the second jumper wire between ground and the seat relay center connector C2 terminal F.

Does the rear vertical motor operate in both directions during each of these conditions?

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Go to Step 11

Go to Step 10

10

  1. Disconnect the RH or LH lower seat motor connector C1.
  2. Use a DMM to measure CKT 282 for continuity between the seat relay center connector C2 terminal F and the seat motor connector C1 terminal E.

Is CKT 282 continuous between these two connectors?

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Go to Step 12

Go to Step 13

11

Replace the RH or LH seat relay center.

Is the repair complete?

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Go to Power Seat System Diagnostic System Check

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12

Locate and repair an open or a high resistance in CKT 282.

Is the repair complete?

--

Go to Power Seat System Diagnostic System Check

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13

Use a DMM to measure CKT 283 for continuity between the seat relay center connector C3 terminal D and the seat motor connector C1 terminal F.

Is CKT 283 continuous between these two connectors?

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Go to Step 14

Go to Step 15

14

Locate and repair an open or a high resistance in CKT 283.

Is the repair complete?

--

Go to Power Seat System Diagnostic System Check

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15

Check carefully for any binding of the rear vertical seat motor and linkage. If OK, replace the RH or LH rear vertical seat motor.

Is the repair complete?

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Go to Power Seat System Diagnostic System Check

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