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B2875




DTC B2850, B2855, B2870, or B2875

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 B2850 01
- Telescope Forward Switch Circuit Short to Battery

DTC B2855 01
- Telescope Rearward Switch Circuit Short to Battery

DTC B2870 01
- Tilt Up Switch Circuit Short to Battery

DTC B2875 01
- Tilt Down Switch Circuit Short to Battery

Diagnostic Fault Information





Circuit Description

The memory seat module (MSM) receives voltage inputs from the tilt/telescope switch based on the position of the switch. The MSM then supplies battery voltage and a ground to the tilt or telescope motor control circuits depending on which direction of movement is requested.

Conditions for Running the DTC

The ignition ON.

Conditions for Setting the DTC

The MSM detects a tilt or telescope switch input for more than 30 consecutive seconds after the tilt or telescope motor movement has stopped.

Action Taken When the DTC Sets

* The tilt or telescope 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* A current DTC will clear when the failed switch input is no longer active.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 tilt or telescope switch may cause a DTC to set.

Reference Information
Schematic Reference

Tilt/Telescoping Steering Column Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Steering Wheel and Column Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, observe the appropriate scan tool Tilt or Telescope Switch parameter while cycling the tilt/telescope switch between states. The parameter should change between Inactive and Active.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the tilt/telescope switch.
2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 1 and ground.

If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Verify the scan tool tilt switch and telescope switch parameters are Inactive.

If not the specified value, test the signal circuits listed below for a short to voltage. If the circuit tests normal, replace the MSM.

* Tilt Up Switch terminal 2
* Tilt Down Switch terminal 6
* Telescope Forward Switch terminal 3
* Telescope Rearward Switch terminal 5

4. Install a 3A fused jumper wire between the signal circuits listed below and the B+ circuit terminal 1. Verify the scan tool tilt switch and telescope switch parameters are Active.

* Tilt Up Switch terminal 2
* Tilt Down Switch terminal 6
* Telescope Forward Switch terminal 3
* Telescope Rearward Switch terminal 5

If not the specified value, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.

5. If all circuit test normal, test or replace the tilt/telescope switch.

Component Testing

Tilt/Telescope Switch
1. Ignition OFF, disconnect the harness connector at the tilt/telescope switch.
2. Test for infinite resistance between the signal terminals listed below and the B+ terminal 1 with the switch in the neutral position:

* Tilt Up Switch terminal 2
* Tilt Down Switch terminal 6
* Telescope Forward Switch terminal 3
* Telescope Rearward Switch terminal 5

If less than the specified range, replace the steering column.

3. Test for less than 1 ohm between the B+ terminal 1 and the signal terminal 2 with the switch in the TILT UP position.

If greater than the specified range, replace the steering column.

4. Test for less than 1 ohm between the B+ terminal 1 and the signal terminal 6 with the switch in the TILT DOWN position.

If greater than the specified range, replace the steering column.

5. Test for less than 1 ohm between the B+ terminal 1 and the signal terminal 5 with the switch in the TELESCOPE OUT position.

If greater than the specified range, replace the steering column.

6. Test for less than 1 ohm between the B+ terminal 1 and the signal terminal 3 with the switch in the TELESCOPE IN position.

If greater than the specified range, replace the steering column.

Repair Instructions

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

* Steering Column Tilt Wheel and Telescope Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning)for MSM replacement, setup, and programming