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B1745



DTC B1745

CIRCUIT DESCRIPTION
When the power seat switches are pressed, they send a 12-volt signal through the switch signal circuits to the memory seat module (MSM). The MSM then commands the driver seat motors or the passenger seat lumbar vertical motor to move in response to the switch signals.

DTC DESCRIPTORSs
This diagnostic procedure supports the following DTCs:
- DTC B1735 Driver Seat Front Up Switch Circuit
- DTC B1740 Driver Seat Front Down Switch Circuit
- DTC B1745 Driver Seat Rear Up Switch Circuit
- DTC B1750 Driver Seat Rear Down Switch Circuit
- DTC B1755 Driver Seat Assembly Horizontal Forward Switch Circuit
- DTC B1760 Driver Seat Assembly Horizontal Rearward Switch Circuit
- DTC B1815 Driver Seat Recline Forward Switch Circuit
- DTC B1820 Driver Seat Recline Rearward Switch Circuit
- DTC B1830 Driver Seat Lumbar Forward Switch Circuit
- DTC B1835 Driver Seat Lumbar Rearward Switch Circuit
- DTC B1840 Driver Seat Lumbar Up Switch Circuit
- DTC B1845 Driver Seat Lumbar Down Switch Circuit
- DTC B2085 Front Passenger Seat Lumbar Up Switch Circuit
- DTC B2090 Front Passenger Seat Lumbar Down Switch Circuit

CONDITIONS FOR RUNNING THE DTC
The MSM must be powered and can not have DTC B1327 Battery Positive Low as an active DTC for this DTC to set.

CONDITIONS FOR SETTING THE DTC
- If a seat switch circuit continues to be active for 30 seconds after a motor controlled by that switch reaches the end of its travel, the switch will be considered shorted and the MSM will set the DTC.
- If a position sensor DTC is current and the associated switch is active for 30 continuous seconds, the switch will be considered shorted and the MSM will set a switch DTC.

ACTION TAKEN WHEN THE DTC SETS
- A motor output driven in response to a switch considered failed, is deactivated for both directions.
- All memory recall commands are ignored.
- The MSM will respond to any other switch signal that has not set a DTC.

CONDITIONS FOR CLEARING THE DTC
The DTC automatically clears when the switch circuit setting the DTC is no longer active.

DIAGNOSTIC AIDS
The scan tool references the memory seat module (MSM) as the driver position module (DPM).

TEST DESCRIPTION

Step 1 - Step 10:




The numbers below refer to the step numbers on the diagnostic table.
2. This step checks the existing state of the seat or lumbar switch by using the current state of the signal parameter. If all of the seat or lumbar switch parameters display active, possibly one of the switch input circuits is shorted to voltage.
4. When the seat or lumbar switch is disconnected, this step determines if the switch contacts are stuck closed, or if one of the switch signal circuits is possibly shorted to battery positive voltage.