Contents Wiring diagrams Section: Memory Modules All sections

Secondary and Configurable Customer Controls: Diagnosis Chevrolet Silverado 2500 HD

Memory Modules ~873 words

DIAGNOSTIC CODE INDEX

DTCDescription
DTC B1529Device Voltage Reference Output Circuit Voltage Threshold
DTC B3622Steering Wheel Controls Signal Circuit

DIAGNOSTIC CODE INDEX

Begin the system diagnosis with the Diagnostic System Check - Vehicle . The Diagnostic System Check - Vehicle will provide the following information

  1. The identification of the control modules which command the system
  2. The ability of the control modules to communicate through the serial data circuit
  3. The identification of any stored DTCs and their status

The use of the Diagnostic System Check - Vehicle will identify the correct procedure for diagnosing the system and where the procedure is located.

Scan Tool Data List

Scan Tool ParameterData ListUnits DisplayedTypical Data Value
Operating Conditions: Ignition ON
SWC Bank 1 StatusData DisplaySW1-SW7Pressed: SW1-SW7, Released: Idle

Scan Tool Data List

Diagnostic Instructions

  1. Perform the «Diagnostic System Check - Vehicle»(ref-278018-S19353494792008012100000) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(ref-278018-S03493196652008012100000) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(ref-278018-S38264170562008012100000) provides an overview of each diagnostic category.

Conditions for Running the DTC

The ignition is ON.

Circuit/System Testing

IMPORTANTIt is recommended that component testing is performed before circuit testing when diagnosing steering wheel controls.
CAUTIONRefer to SIR Caution .
  1. Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
  2. Ignition ON, test for ignition voltage between the ignition circuit terminal 2 and ground. If less than specified value, test the ignition circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM.
  3. Test for the 0 volts between the signal circuit terminal 1 and ground. If greater than specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  4. Test for ignition voltage between the ignition circuit terminal 2 and the signal circuit terminal 1. If less than specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
  5. Ignition OFF, disconnect the X1 harness connector at the BCM.
  6. Test for infinite resistance between the signal circuit terminal 6 and ground. If less than specified value, test the signal circuit for a short to ground.
  7. If all circuits test normal, test or replace switch.

Component Testing

CAUTIONRefer to SIR Caution .
  1. Ignition OFF, disconnect the harness connector at the suspect steering wheel control switch.
  2. Test for infinite resistance between the ignition terminal 2 and the signal terminal 1 with the switch in the open position. If less than specified value, replace the switch.
  3. Test for less than 5,400 ohms of resistance between the signal terminal 1 and the ignition terminal 2 with the switch in the closed position. If greater than the specified value, replace the steering wheel control switch.
  1. Perform the «Diagnostic System Check - Vehicle»(ref-278018-S19353494792008012100000) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(ref-278018-S03493196652008012100000) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(ref-278018-S38264170562008012100000) provides an overview of each diagnostic category.

Ignition ON.

Conditions for Setting the DTC

BCM detects voltage above 18.5 volts for 100 msec.

Action Taken When the DTC Sets

BCM will ignore the switch command.

Conditions for Clearing the DTC

  1. The condition for setting the DTC is no longer present and the DTC is cleared with a scan tool.
  2. The BCM automatically clears the history DTC when a current DTC is not detected in 100 consecutive ignition cycles.

Diagnostic Aids

Test the charging system. Refer to Charging System Test .

IMPORTANTPerform the Diagnostic System Check - Vehicle before using the Symptom Tables in order to verify that all of the following conditions are true: There are no DTCs set. The control modules can communicate via the serial data link. Review the system operation in order to familiarize yourself with the system functions. Refer to Steering Wheel Controls Description and Operation .

Visual/Physical Inspection

  1. Inspect for aftermarket devices which may affect the operation of the Steering Wheel Controls System. Refer to «Checking Aftermarket Accessories»(ref-278019-S10639375482008012100000) .
  2. Inspect for easily accessible or visible system components for obvious damage or conditions which may cause the symptom.

Symptom List

Refer to Steering Wheel Controls Inoperative in order to diagnose the symptom.

  1. Perform the «Diagnostic System Check - Vehicle»(ref-278018-S19353494792008012100000) prior to using this diagnostic procedure.
  2. Review «Strategy Based Diagnosis»(ref-278018-S03493196652008012100000) for an overview of the diagnostic approach.
  3. «Diagnostic Procedure Instructions»(ref-278018-S38264170562008012100000) provides an overview of each diagnostic category.
  1. This diagnostic is for the audio steering wheel controls.
  2. Before diagnosis of the steering wheel controls, ensure the primary controls of the associated component are functioning properly.
IMPORTANTIt is recommended that component testing is performed before circuit testing when diagnosing steering wheel controls.
  1. Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
  2. Ignition ON, test for ignition voltage between the ignition circuit terminal 4 and ground. If less than specified value, test the ignition circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the BCM.
  3. Test for the 0 volts between the signal circuit terminal 3 and ground. If greater than specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the BCM.
  4. Test for ignition voltage between the ignition circuit terminal 4 and the signal circuit terminal 3. If less than specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.
  5. Ignition OFF, disconnect the harness connector X1 at the BCM.
  6. Test for infinite resistance between the signal circuit terminal 6 and ground. If less than specified value, test the signal circuit for a short to ground.
  7. If all circuits test normal, test or replace switch.
  1. Ignition OFF, disconnect the harness connector at the right steering wheel control switch.
  2. Test for infinite resistance between the ignition terminal 4 and the signal terminal 3 with the switch in the open position. If less than the specified value, replace the switch.
  3. Test for less than 5400 ohms between the ignition terminal 4 and the signal terminal 3 with the switch in the closed position. If greater than the specified value, replace the switch.