B2858

DTC B2853, B2858, B2873, or B2878

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B2853

-
Telescope Forward Switch Circuit High

DTC B2858

-
Telescope Rearward Switch Circuit High

Diagnostic Fault Information






Circuit/System Description

The memory seat module - driver receives voltage inputs from contacts inside the telescope switch. The memory seat module - driver then supplies battery voltage to the telescoping drive motor forward or reverse circuit depending on which direction of movement is requested. The motor is reversible and voltage is applied to either circuit to accomplish movement in opposite directions. The memory seat module - driver monitors the position and movement of the telescoping drive motor on the telescope signal circuit.

Conditions for Running the DTC

Ignition ON

Conditions for Setting the DTC

The memory seat module - driver detects a switch input for more than 30 consecutive seconds after movement of the telescoping drive motor in the requested direction has stopped.

Action Taken When the DTC Sets

* The telescoping drive motor will be deactivated.

* Memory recall functions will be disabled.

Conditions for Clearing the DTC

* A current DTC will clear when the failed switch input is no longer active.

* A history DTC will clear after 100 ignition cycles.

Diagnostic Aids

An intermittently stuck switch can cause this DTC to set. Also, the driver can cause this DTC to set by holding the telescope switch for 30 seconds after the column reaches the end of its travel.

Reference Information

Schematic Reference

Tilt/Telescoping Steering Column Schematics Tilt/Telescoping Steering Column Schematics

Connector End View Reference

* Component Connector End Views 5 Bow Lowered Switch (CM7)

* Splice Pack Connector End Views JX205

* Inline Harness Connector End Views X102

Description and Operation

Steering Wheel and Column Description and Operation Description and Operation

Electrical Information Reference

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Circuit Testing Circuit Testing

Scan Tool Reference

Control Module References Control Module References

Circuit/System Verification

Ignition ON, observe the scan tool Telescope Forward Switch and Telescope Rearward Switch parameters in the Driver Position Module Data Display. The reading should be Inactive for both parameters when the switch is not pressed.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector X2 at the memory seat module - driver.

2. Ignition OFF, test for less than 1 volt on both of the telescope switch signal circuits terminals A9 and A10.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the telescope switch.

3. If all circuits test normal, test or replace the memory seat module - driver.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

* Steering Column Telescope Switch Replacement Steering Column Telescope Switch Replacement

* Control Module References Control Module References for memory seat module - driver replacement, setup, and programming