GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1998 🢒 LeSabre 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Boost Gage Malfunction

Step

Action

Value(s)

Yes

No

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Instrument Cluster System Check

2
  1. Turn off the ignition switch.
  2. Disconnect the boost/MAP sensor connector.
  3. Turn the ignition to the RUN position.
  4. Measure the voltage from the boost/MAP sensor connector terminal C to ground.

Is the voltage within the specified value?

5 V

Go to Step 3

Go to Step 4

3

Measure the voltage from the boost/MAP sensor connector terminal C to terminal A.

Is the voltage within the specified value?

5 V

Go to Step 7

Go to Step 8

4
  1. Inspect CKT 705 and CKT 910 (GRY) for an open or a short to ground.
  2. Inspect connector C101 for proper terminal contact at terminal D6.
  3. Inspect the instrument cluster connector C1 for proper terminal contact at terminal B7.

Did you find a wiring or connection condition?

--

Go to Step 5

Go to Step 6

5

Repair the wiring or poor terminal connections.

Is the repair complete?

--

Go to Step 6

--

6

Replace the instrument cluster. Refer to one of the following procedures:

    • For Buick only, refer to Instrument Cluster Replacement .
    • For Oldsmobile only, refer to Instrument Cluster Replacement .
    • For Pontiac only, refer to Instrument Cluster Replacement .

Is the replacement complete?

--

System OK

Go to Instrument Cluster System Check

7

Connect a fused jumper from boost/MAP sensor connector terminal C to terminal B.

Does the boost gauge meet the specified value?

+10

Go to Step 10

Go to Step 11

8
  1. Inspect CKT 251 (BLK/WHT) wiring for an open.
  2. Inspect connector C101 for proper terminal contact at terminal A1.

Did you find a wiring or connection condition?

--

Go to Step 9

Go to Instrument Cluster System Check

9

Repair the wiring or connection.

Is the repair complete?

--

Go to Instrument Cluster System Check

--

10

Inspect the boost/MAP sensor connector for proper terminal contact.

Is the terminal contact OK?

--

Go to Step 12

Go to Step 11

11
  1. Inspect CKT 891 (BLK) for an open or short to ground.
  2. Inspect connector C101 for proper terminal contact at F7.
  3. Inspect the instrument cluster connector C2 for proper terminal contact at B11.

Did you find a wiring or connection condition?

--

Go to Step 13

Go to Step 14

12

Replace the boost/MAP sensor. Refer to the appropriate procedure:

Is the repair complete?

--

Go to Instrument Cluster System Check

--

13

Repair the wiring or connection condition.

Is the repair complete?

--

Go to Step 14

--

14

Replace the instrument cluster (IPC). Refer to one of the following procedures:

    • For Buick only, refer to Instrument Cluster Replacement .
    • For Oldsmobile only, refer to Instrument Cluster Replacement .
    • For Pontiac only, refer to Instrument Cluster Replacement .

Is the repair complete?

--

Go to Instrument Cluster System Check

--