The driver door switch assembly (DDSA) receives voltage inputs from the telescope switch based on the position of the switch. The DDSA sends a class 2 serial data message to the memory seat module (MSM). The MSM supplies battery voltage and ground to the telescope motor control circuits depending on which direction of movement is requested.

The 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.

Schematic Reference

Column Lock Schematics

Connector End View Reference

Description and Operation

Steering Wheel and Column Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References

1. Ignition ON, observe the scan tool Telescope Forward Switch and Telescope Rearward Switch parameters while cycling the telescope switch between the TELESCOPE IN, and TELESCOPE OUT positions. The appropriate parameter should cycle between Active and Inactive.

⇒	If any of the parameters do not cycle between the specified values, refer to Telescope Switch Circuit Malfunction.

2. Observe the scan tool Telescope Sensor parameter. The reading should be between 0.2 and 4.8 volts.

⇒	If not within the specified range, refer to Telescope Sensor Circuit Malfunction.

3. Command the column to telescope in and out using the telescope switch. The column should move in the commanded direction.

⇒	If the column does not operate as specified, refer to Telescope Actuator Circuit Malfunction.

Telescope Switch Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the telescope switch.
2. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal C 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 all the scan tool telescope switch parameters are Inactive.

•	Telescope Forward Switch - signal circuit terminal B

•	Telescope Reverse Switch - signal circuit terminal A

⇒	If any of the parameters are not the specified value, test the appropriate signal circuit terminal for a short to voltage. If the circuit tests normal, replace the DDSA.

4. Install a 3A fused jumper wire between the appropriate signal circuit terminal and the B+ circuit terminal C. Verify the appropriate scan tool telescope switch parameter is Active.

•	Telescope Forward Switch - signal circuit terminal B

•	Telescope Reverse Switch - signal circuit terminal A

⇒	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 DDSA.

5. If all circuits test normal, test or replace the telescope switch.

Telescope Sensor Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the appropriate telescope actuator.
2. Ignition OFF, test for less than 2.0 ohms of resistance between the low reference circuit terminal E and ground.

⇒	If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the MSM.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal D and ground.

⇒	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.

4. Verify the appropriate scan tool telescope sensor parameter is less than 0.2 volts.

⇒	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.

5. Install a 3A fused jumper wire between the signal circuit terminal C and the 5-volt reference circuit terminal D. Verify the appropriate scan tool telescope sensor parameter is greater than 4.8 volts.

⇒	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.

6. If all circuits test normal, test or replace the appropriate telescope actuator.

Telescope Actuator Circuit Malfunction

1. Ignition OFF, disconnect the harness connector at the telescope actuator.
2. Install a test lamp between the control circuit terminal A and the control circuit terminal B.
3. Command the column to telescope in and out using the telescope switch. The test lamp should illuminate with each command.

⇒	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.

4. If all circuits test normal, test or replace the telescoping actuator.

Telescope Switch

1. Ignition OFF, disconnect the harness connector at the telescope switch.
2. Test for infinite resistance between the following terminals with the switch in the neutral position:

•	B+ terminal F and signal terminal A

•	B+ terminal F and signal terminal B

⇒	If less than the specified range, replace the telescope switch.

⇒	If greater than the specified range, replace the telescope switch.

3. Test for less than 1 ohm or resistance between the B+ terminal C and the signal terminal A with the switch in the TELESCOPE OUT position.

⇒	If greater than the specified range, replace the telescope switch.

4. Test for less than 1 ohm or resistance between the B+ terminal C and the signal terminal B with the switch in the TELESCOPE IN position.

⇒	If greater than the specified range, replace the telescope switch.

Telescoping Actuator

1. Ignition OFF, disconnect the harness connector at the telescoping actuator.
2. Test for less than 2.0 ohms of resistance between the control terminal A and the control terminal B.

⇒	If greater than the specified range, replace the telescoping actuator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.