GM Service Manual Online
For 1990-2009 cars only

Object Number: 259749  Size: MF
Radio/Audio System Circuit Description
Cell 150: Power and Ground
Cell 150: Power and Ground
Handling ESD Sensitive Parts Notice
Power Distribution Schematics
Power Distribution Schematics
Ground Distribution Schematics

Circuit Description

Battery positive voltage (B+) is supplied via CKT 2240 (ORN) to the radio (IRC) at terminal F1. The radio monitors this voltage to determine if it is within a valid operating range.

Conditions for Setting the DTC

The battery positive voltage (B+) rises above 15.5 volts for more than approximately 1.2 seconds.

Action Taken When the DTC Sets

    • Stores a DTC B1982 in the radio memory.
    • The radio does not respond to inputs when the voltage is greater than 16 volts.
    • No driver warning message is displayed for this DTC.

Conditions for Clearing the DTC

The battery positive voltage (B+) level falls below 15 volts for approximately 1.2 seconds.

Diagnostic Aids

This DTC may set when the vehicle is placed on a battery charger, on fast charge, for a long period of time.

Test Description

The numbers below refer to the step numbers on the diagnostic table:

  1. Perform the Radio/Audio System Diagnostic System Check before continuing with the diagnosis of this DTC.

  2. Checks that DTC was not set erroneously.

  3. Determines whether the malfunction is in the charging system or the radio (IRC).

  4. Clear all DTCs after the repair procedure is complete.

IRC DTC B1982 -- Source/Battery Voltage High

Step

Action

Value(s)

Yes

No

1

Was the Radio/Audio System Diagnostic System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - Radio/Audio System

2

  1. Turn the ignition switch to ON.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select data from the radio (IRC) data list.

Is the battery positive voltage (B+) less than the specified value?

15.5 V

Go to Step 4

Go to Step 3

3

  1. Turn the ignition switch to OFF.
  2. Disconnect the radio connector.
  3. Measure the voltage between the radio connector terminal F1 and ground.

Is the measured voltage greater than the specified value?

15.5 V

Go to Charging System Check in Engine Electrical

Go to Step 4

4

Replace the radio. Refer to Radio Replacement .

Is the replacement complete?

--

Go to Step 5

--

5

  1. Turn the ignition switch to OFF.
  2. Reconnect or install any connectors or components that were disconnected or removed.
  3. Turn the ignition switch to ON.
  4. Clear any DTCs. Refer to Clearing DTCs .

Are all DTCs cleared?

--

Go to Diagnostic System Check - Radio/Audio System

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