GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Alero Export 🢒 Body and Accessories 🢒 Instrument Panel, Gauges, and Console 🢒 Diagnostic System Check - Instrument Cluster

Circuit Description

The instrument panel cluster (IPC) diagnostic system check aids in diagnosing an electronic system malfunction. The IPC diagnostic system check is the starting point for any IPC complaints. Understanding and using the IPC the following table will reduce diagnostic time and prevent the unnecessary replacement of parts.

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

  1. This step determines if the data link connector can power the scan tool up.

  2. This step determines if communications can be established with the IPC.

  3. This step determines if the class 2 line is operational and can communicate to other modules on the line.

  4. This step determines if CKT 1440 is shorted to ground and opens the IPC/HVAC BATT fuse.

  5. This step determines if CKT 1440 is still shorted to ground or if it was an intermittent problem.

  6. This step determines if CKT 1600 is shorted to ground and opens the IPC/BFC/ACC IGN 0 fuse.

  7. This step determines if CKT 1600 is still shorted to ground or if it was an intermittent problem.

  8. This step determines if the IPC CKT 1440 is open between the IPC/HVAC BATT fuse.

  9. This step determines if the IPC CKT 1600 is open between the IPC and the IPC/BFC/ACC fuse.

  10. This step determines if the IPC ground CKT 151 is open.

  11. This step determines if the IPC class 2 CKT 1807 is open between the IPC and the data line connector.

Important: After a repair is made that requires clearing the DTCs from the IPC, the repair must be inspected by operating the vehicle within the limits shown in Conditions For Setting the DTC. This portion of the procedure will verify that the repair was made correctly.

Important: The probing of electrical circuits without the use of the J35616-A Connector Test Adapter Kit may cause damage to the electrical components and connectors. The Adapter Kit is the only recommended method of probing connectors, terminals and junction block. The Adapter Kit contains an assortment of flexible connectors used in order to probe connectors, terminals and junction block during diagnosis.

Step

Action

Value(s)

Yes

No

1

Plug the scan tool into the data link connector (DLC).

Does power exist?

--

Go to Step 2

Go to Scan Tool Will Not Communicate with a Class 2 Device

2

With the scan tool, attempt to establish communications with the instrument cluster.

Does the scan communicate with the instrument cluster?

--

Go to Instrument Cluster System Check

Go to Step 3

3

Attempt to establish communications with other class 2 systems (PCM, BCM).

Does the scan tool communicate with other class 2 systems?

--

Go to Step 4

Go to Scan Tool Will Not Communicate with a Class 2 Device

4

Inspect the IPC/HVAC BATT fuse for an open?

Does the condition exist?

--

Go to Step 5

Go to Step 7

5
  1. Turn the ignition to the OFF position.
  2. Replace the open fuse.
  3. Turn the ignition to the RUN position.
  4. Recheck the open fuse.

Does the condition exist?

--

Go to Step 6

Go to Intermittent and Poor Connections Diagnosis

6
  1. Verify CKT 1440 is shorted to ground. Refer to Power Distribution in order to determine the other components located on CKT 1440.
  2. Disconnect each component 1 at a time in order to determine which component is shorted to ground. If all the components are OK, locate and repair the short to ground in CKT 1440 (ORN).

Did you complete the repair?

--

Go to Step 19

--

7

Inspect the IPC/BFC/ACC fuse for an open.

Does the condition exist?

--

Go to Step 8

Go to Step 10

8
  1. Turn the ignition switch to the OFF position.
  2. Replace the open fuse.
  3. Turn the ignition to the RUN position.
  4. Recheck the IPC/BFC/ACC fuse for an open.

Does the condition exist?

--

Go to Step 9

Go to Intermittents and Poor Connections Diagnosis

9
  1. Verify CKT 1600 is shorted to ground. Refer to Power Distribution in order to determine the other components located on CKT 1600.
  2. Disconnect each component 1 at a time in order to determine which component is shorted to ground. If all the components are OK, locate and repair the short to ground in CKT 1600 (PPL).

Did you complete the repair?

--

Go to Step 19

--

10
  1. Turn the ignition to the OFF position.
  2. Disconnect the IPC connector and remove the connector combs.
  3. Turn the ignition to the RUN position.
  4. Backprobe in order to prevent damage to the terminal with a digital multimeter (DMM).

    5. Measure the voltage between CKT 1440 (ORN) cavity A12 and ground.

Does the DMM display battery voltage?

--

Go to Step 11

Go to Step 14

11
  1. Using a DMM, backprobe in order to prevent damage to the terminal.
  2. Measure the voltage between CKT 1600 (PPL) cavity A8 and ground.

Does the DMM display battery voltage?

--

Go to Step 12

Go to Step 15

12
  1. Using a DMM, backprobe in order to prevent damage to the terminal.
  2. Measure the voltage between CKT 1600 (PPL) cavity A8 and CKT 151 (BLK/WHT) cavity A6 of the IPC connector.

Does the DMM display battery voltage?

--

Go to Step 13

Go to Step 16

13

Using a DMM, measure the resistance between CKT 1807 (GRY) cavity A9 of the IPC connector and cavity 2 of the data line connector.

Does the resistance measure within the specified range?

0-2 ohms

Go to Step 18

Go to Step 17

14

Locate and repair the open in CKT 1400 (ORN) between the IPC and the IPC/HVAC/BATT fuse.

Did you locate and repair the condition?

--

Go to Step 19

--

15

Locate and repair the open in CKT 1600 (PPL) between the IPC and the IPC/BFC/ACC fuse.

Did you locate and repair the condition?

--

Go to Step 19

--

16

Locate and repair the open in CKT 151 (BLK/WHT) between the IPC and G202.

Did you locate and repair the condition?

--

Go to Step 19

--

17

Locate and repair the open in CKT 1400 (ORN) between the IPC and the IPC/HVAC/BATT fuse.

Did you locate and repair the condition?

--

Go to Step 19

--

18

Replace the instrument cluster.

Did you complete the repair?

--

Go to Step 19

--

19
  1. Turn the ignition switch to the OFF position.
  2. Reconnect all disconnected components.
  3. Use the scan tool in order to clear all the DTCs.

Are all the DTCs cleared?

--

Go to Instrument Cluster System Check