GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The compass display is part of the driver information center (DIC) within the IPC. The IPC and the electronic compass module communicate on a two wire serial peripheral interface (SPI). The IPC controls the compass clock signal circuit which is used for the communication timing between the IPC and the electronic compass module. The compass information is transmitted on the bi-directional compass data signal circuit. The SPI is idle when the compass clock signal circuit is high and the compass data signal circuit is low.

Conditions for Running the DTC

    • The ignition is ON.
    • B1327 is not set.

Conditions for Setting the DTC

The IPC does not detect the electronic compass module for greater than 4 seconds.

Action Taken When the DTC Sets

The compass display is blank.

Conditions for Clearing the DTC

    • The DTC becomes history when the conditions for setting the DTC are no longer present.
    • The history DTC clears after 50 malfunction free ignition cycles.
    • The IPC receives a clear code command from the scan tool.

Step

Action

Value(s)

Yes

No

Schematic Reference: Instrument Cluster Schematics

1

Did you perform the Instrument Cluster Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Instrument Cluster

2

Turn ON the ignition, with the engine OFF.

Does the compass operate properly?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the electronic compass module.
  3. Connect a test lamp between the ignition 3 voltage circuit and a good ground.
  4. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

--

Go to Step 4

Go to Step 13

4

Connect a test lamp between the ignition 3 voltage circuit and the ground circuit of the electronic compass module.

Does the test lamp illuminate?

--

Go to Step 5

Go to Step 14

5

Measure the voltage between the compass clock signal circuit and a good ground.

Does the voltage measure greater than the specified value?

9 V

Go to Step 6

Go to Step 7

6

Measure the voltage between the compass data signal circuit and a good ground.

Does the voltage measure less than the specified value?

3 V

Go to Step 8

Go to Step 10

7

Test the compass clock signal circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 12

8

Test the compass clock signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 9

9

Test the compass data signal circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 11

10

Test the compass data signal circuit for an open, a high resistance, or a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 11

11

Inspect for poor connections at the harness connector of the electronic compass module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 15

12

Inspect for poor connections at the harness connector of the IPC. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 17

Go to Step 16

13

Repair the short to ground, the open, or the high resistance in the ignition 3 voltage circuit of the electronic compass module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 17

--

14

Repair the open or the high resistance in the ground circuit of the electronic compass module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 17

--

15

Important: Perform the calibration and variance procedure for the replacement electronic compass module.

Replace the electronic compass module. Refer to Electronic Compass Module Replacement .

Did you complete the replacement?

--

Go to Step 17

--

16

Replace the IPC. Refer to Instrument Cluster Replacement .

Did you complete the replacement?

--

Go to Step 17

--

17

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK