GM Service Manual Online
For 1990-2009 cars only

Object Number: 313527  Size: MF
Instrument Cluster and HUD Components
Cell 81: Driver Information and Head Up Display

Circuit Description

When you press the RESET switch, circuit 1816 grounds. The instrument cluster detects the ground on terminal B9. The instrument cluster resets the appropriate display data (i.e. trip odometer, fuel data, oil life index, etc.).

Conditions for Setting the DTC

DTC B1520 sets under the following conditions:

    • The ignition is in RUN.
    • The RESET switch is stuck or shorted to ground for greater than 60 seconds.

Action Taken When the DTC Sets

When DTC B1520 sets, one of the following actions occur:

    • The instrument cluster disables the function of the RESET switch for the remainder of that ignition cycle.
    • The DTC is set as a history DTC.
    • The instrument cluster resets any display data.

Diagnostic Aids

Test for a binding, sticking or broken RESET switch. If the RESET switch is OK, clear the DTC. Perform the System Check. If the DTC is set current again, refer to DTC B1520 Reset Switch Stuck/Shorted To Ground diagnostic table.

Step

Action

Value(s)

Yes

No

1

  1. Use a scan tool to clear the DTC.
  2. Turn the ignition switch to OFF.
  3. Disconnect the switch.
  4. Turn the ignition switch to RUN.
  5. Wait for 60 seconds.
  6. Use a scan tool to test for DTC B1520

Is the DTC present?

--

Go to Step 2

Go to Step 3

2

Repair the open or short to ground in CKT 1325.

Is the repair complete?

--

Go to Diagnostic System Check - Instrument Cluster

--

3

Test the resistance between terminal G and terminal H (2 button switch) or between terminal B and terminal H (5 button switch).

Is the resistance within the specified range?

0-5 ohms

Go to Step 4

Go to Intermittents and Poor Connections Diagnosis

4

Replace the DIC switch.

Is the repair complete?

--

Go to Diagnostic System Check - Instrument Cluster

--