GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B2860 01: Telescope Position Sensor Circuit Short to Battery

DTC B2860 06: Telescope Position Sensor Circuit Short to Ground or Open

DTC B2860 5A: Telescope Position Sensor Circuit Plausibility Failure

DTC B2860 61: Telescope Position Sensor Actuator Stuck

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

5 Volt Reference

B2860 06, B2880 06

B2860 06, B2880 06

B2860 01, B2880 01

--

Steering Column Tilt Sensor Signal

B2880 06

B2880 06

B2880 01

B2880 5A

Steering Column Telescope Sensor Signal

B2860 06

B2860 06

B2860 01

B2860 5A

Steering Column Tilt Motor Control - Up

B2880 61

B2880 61

B2880 61

--

Steering Column Tilt Motor Control - Down

B2880 61

B2880 61

B2880 61

--

Steering Column Telescope Motor Control - Forward

B2860 61

B2860 61

B2860 61

--

Steering Column Telescope Motor Control - Reverse

B2860 61

B2860 61

B2860 61

--

Low Reference

--

B2860 06, B2880 06

B2860 01

--

Circuit Description

The memory seat module (MSM) determines the position of the steering column based on inputs received from the telescope position sensor, built into the telescoping actuator. The MSM supplies a 5-volt reference and a low reference to the sensor and monitors the column position via the steering column telescope sensor signal circuit.

Conditions for Running the DTC

Ignition ON

Conditions for Setting the DTC

B2860 01

The steering column telescope sensor signal voltage is greater than 4.8 volts for more than 2 seconds.

B2860 06

The steering column telescope sensor signal voltage is less than 0.2 volts for more than 2 seconds.

B2860 5A

An incorrect steering column telescope sensor signal voltage is seen.

B2860 61

The steering column telescope sensor signal voltage does not change when the telescope actuator is commanded.

Action Taken When the DTC Sets

Steering column telescope operation are suspended.

Conditions for Clearing the DTC

    • A current DTC will clear when the malfunction is no longer present
    • A history DTC will clear after 40 malfunction-free ignition cycles.

Diagnostic Aids

The power column features such as the power tilt/telescope switch, tilt/telescope actuator, and tilt/actuator assembly are internal to the steering column and only replaced as a complete unit. So any power actuator or switch replacement can only be done as a complete unit.

Reference Information

Schematic Reference

Tilt/Telescoping Steering Column Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Steering Wheel and Column Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for Scan Tool Information

Circuit/System Verification

  1. Ignition ON, observe the scan tool Telescope Forward Switch and Telescope Rearward Switch parameters while cycling the tilt/telescope switch between the TELESCOPE IN and TELESCOPE OUT positions. The parameters should cycle between Active and Inactive.
  2. If the parameters do not cycle between the specified values, refer to Steering Column Tilt/Telescoping Inoperative .
  3. Observe the scan tool Telescope Sensor parameter. The reading should be between 0.2 and 4.8 volts.
  4. If not within the specified range, refer to Telescope Sensor Circuit Malfunction.
  5. Command the column to telescope in and out using the tilt/telescope switch. The column should move forward and rearward.
  6. If the column does not operate as specified, refer to Telescoping Actuator Circuit Malfunction.

Circuit/System Testing

Telescope Sensor Circuit Malfunction

  1. Ignition OFF, disconnect the harness connector X2 at the telescoping actuator.
  2. Ignition OFF, test for less than 2.0 ohms between the low reference circuit terminal B and ground.
  3. If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal C and ground.
  5. If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
    If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  6. Verify the scan tool Telescope Sensor parameter is less than 0.2 volt.
  7. If greater than the specified range, test the signal circuit terminal C for a short to voltage. If the circuit tests normal, replace the MSM.
  8. Install a 3A fused jumper wire between the telescope motor signal circuit terminal C and the 5-volt reference circuit terminal C. Verify the scan tool Telescope Sensor parameter is greater than 4.8 volts.
  9. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
  10. If all circuits test normal, test or replace the steering column.

Telescoping Actuator Circuit Malfunction

  1. Ignition OFF, disconnect the inline harness connector X201 inline with harness connector X1 at the telescoping actuator.
  2. Install a test lamp between the motor control circuit terminal 1 and the motor control circuit terminal 3.
  3. Command the column to telescope in and out using the tilt/telescope switch. The test lamp should illuminate with each command.
  4. If the test lamp does not illuminate, test both control circuits for a short to ground or an open/high resistance. If the circuits test normal, replace the MSM.
  5. If all circuits test normal, test or replace the steering column.

Component Testing

Telescoping Actuator

  1. Ignition OFF, disconnect the harness inline connector X201 inline with connector X1 at the telescoping actuator.
  2. Test for less than 2.0 ohms between the control terminal 1 and the control terminal 3.
  3. If greater than the specified range, replace the steering column.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Steering Column Replacement
    •  Control Module References for MSM replacement, setup, and programming