GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 Riviera 🢒 Body and Accessories 🢒 Seats 🢒 Power Seat Inoperative

Power Seat Inoperative With A45

Step

Action

Value(s)

Yes

No

1

Was the entire Memory Seats System Check performed?

--

Go to Step 2

Go to Memory Seats System Check

2
  1. Turn the ignition switch to the OFF position.
  2. Connect a fused jumper from the memory seat/mirror diagnostic connector to ground (the connector may be taped up into the body harness).
  3. Listen for a chime that acknowledges entrance into mode 1 diagnostics.

Does the memory seat/mirror module chime once and enter diagnostic mode?

--

Go to Step 4

Go to Step 3

3

Inspect CKT 571 (YEL/BLK) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 571 OK?

--

Go to Step 4

Go to Step 13

4
  1. Refer to Memory Seat Circuit Description for a detailed explanation of the memory seat/mirror diagnostic modes.
  2. Operate the left seat switch in all directions.

    3. The module will chime once for each switch input that the module receives.

  3. Any time a switch is operated and the module does not chime, the module did not receive an input from that switch.

Were there any switch operations where the memory seat/mirror module sounded a chime?

--

Go to Step 5

Go to Step 6

5

Diagnose each suspect switch separately.

Refer to Power Seat Inoperative in One Direction .

Is the repair complete?

--

Go to Memory Seats System Check

--

6
  1. Disconnect the left seat switch connector.

    2. For Buick vehicles, the left seat switch connector is C306.

  2. On Buick vehicles, connect a J 39200 digital multimeter (DMM) from connector C306 cavity A (ORN) to ground.
  3. On Oldsmobile vehicles, connect a J 39200 DMM from left seat switch connector cavity B (ORN) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step 11

7
    • On Buick vehicles, connect a J 39200 DMM from the left seat switch connector C306, cavity A (ORN) to cavity E (BLK).
    • On Oldsmobile vehicles, connect a J 39200 DMM from the left seat switch connector cavity B (ORN) to cavity D (BLK).

Is the voltage measured within the specified range?

10-15 V

Go to Step 8

Go to Step 12

8
    • On Buick vehicles, briefly connect a fused jumper from the left seat switch connector C603, cavity A (ORN) to cavity G (TAN).
    • On Oldsmobile vehicles, briefly connect a fused jumper from the left seat switch connector cavity B (ORN) to cavity L (TAN).

Does the left seat move forward while the fused jumper was connected?

--

Go to Step 10

Go to Step 9

9

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

Is the repair complete?

--

Go to Memory Seats System Check

--

10

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

Is the repair complete?

--

Go to Memory Seats System Check

--

11
    • On Buick vehicles, repair the open in CKT 1340 (ORN) between S339 and the left seat switch.
    • On Oldsmobile vehicles, repair the open in CKT 40 (ORN) between S211 and the left seat switch.

Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Memory Seats System Check

--

12

Repair the open in CKT 150 (BLK) between S290 and the left seat switch. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Memory Seats System Check

--

13

Repair the open in CKT 571 (YEL/BLK). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Memory Seats System Check

--

Power Seat Inoperative Without A45

Step

Action

Value(s)

Yes

No

1

Was the entire Power Seats System Check performed?

--

Go to Step 2

Go to Power Seats System Check

2

Inspect CKT 1340 (ORN) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 1340 OK?

--

Go to Step 3

Go to Step 5

3

Inspect CKT 150 (BLK) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 150 OK?

--

Go to Step 4

Go to Step 5

4

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

Is the repair complete?

--

Go to Power Seats System Check

--

5

Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Power Seats System Check

--