For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 | Did you perform the Instrument Cluster Diagnostic System Check? | -- | Go to Step 2 | Go to Diagnostic System Check - Instrument Cluster
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 | Inspect CKT 705 (GRY) for an open or a short to ground. Is the wiring OK? | -- | Go to Step 6 | Go to Step 7
5 | Repair the open on CKT 705 (GRY). Is the repair complete? | -- | Go to Instrument Cluster System Check | --
6 |

1. Inspect connector C101 for proper terminal contact at terminal D6.
2. Inspect the instrument cluster connector C1 for proper terminal contact at terminal B7.

Are the terminals OK?

--

Go to Step 14

Go to Step 15

7 | Connect a fused jumper from boost/MAP sensor connector terminal C to terminal B. Does the boost gauge meet specified value? | +10 | Go to Step 10 | Go to Step 11
8 | Inspect CKT 251 (BLK/WHT) wiring for an open. Is the wiring OK? | -- | Go to Step 16 | Go to Step 9
9 | Repair the open in CKT 251 (BLK/WHT). 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 15
11 | Inspect CKT 891 (BLK) for an open or short to ground. Is the wiring OK? | -- | Go to Step 13 | Go to Step 17
12 | Replace the boost/MAP sensor. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
13 | Repair the open in CKT 891 (BLK). Is the repair complete? | -- | Go to Instrument Cluster System Check | --
14 | Replace the instrument cluster (IPC).

• | 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

--

15 | Repair the poor terminal contact. Is the repair complete? | -- | Go to Instrument Cluster System Check | --
16 | Inspect connector C101 for proper terminal contact at terminal A1. Is the connector terminal contact OK? | -- | Go to Instrument Cluster System Check | Go to Step 15
17 |

1. Inspect connector C101 for proper terminal contact at terminal F7.
2. Inspect the instrument cluster connector C2 for proper terminal contact at B11.

Are the terminal contacts OK?

--

Go to Step 14

Go to Step 15