Circuit Description
The memory seat module (MSM) receives an input from the left lumbar switch when the in switch is actuated. When the lumbar switch is operated in the in direction, battery positive voltage (B+) is supplied to the MSM lumbar in input via CKT 466 (GRY). The MSM recognizes the input and moves the lumbar support in and away from the driver's back.
Conditions for Setting the DTC
| • | When the lumbar in switch is active for 30 seconds after motion has ceased, the switch is considered shorted and the DTC sets. |
| • | If the lumbar horizontal position sensor DTC B2119 is current and the lumbar in switch is active for 30 seconds, the switch is considered shorted and the DTC sets. |
| • | DTC B2109 sets only if DTC B1982 MSM or DTC B1983 MSM is not current. |
Action Taken When the DTC Sets
| • | The MSM does not move the lumbar support in, away from the driver's back. |
| • | The MSM continues to respond to valid inputs from the other manual switches. |
| • | All memory recall function commands are ignored for all directions. |
Conditions for Clearing the DTC
| • | The MSM sees that the lumbar in switch is no longer active. |
| • | Use the on-boards clearing DTCs feature. |
| • | Use a scan tool. |
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
Perform the entire Power Seat Systems Diagnostic System Check before continuing with the diagnosis of this DTC.
-
This step determines if a switch is stuck or if a short to battery positive voltage (B+) exists in the wiring input to the memory seat module (MSM). DTC B2109 will set again if a short in the wiring exists or if an internal MSM problem exists. DTC B2109 will not set again if a switch is stuck because the switch has been disconnected from the memory seat module (MSM) input.
-
This step determines if a short to battery positive voltage (B+) exists in the input wiring to the MSM.
-
Clear all DTCs after the repair procedure is complete.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Was the entire Power Seat Systems Diagnostic System Check performed? | -- | |||
After 30 seconds, does DTC B2109 reset? | -- | |||
Is the voltage within the specified range? | 10-15 V | |||
4 | Replace the memory seat module (MSM). Refer to Memory Seat Control Module Replacement . Is the MSM replacement complete? | -- | -- | |
5 | Replace the LH lumbar switch. Is the lumbar switch replacement complete? | -- | -- | |
6 | Repair the short to battery positive voltage (B+) in CKT 466 (GRY). Refer to Wiring Repairs in Wiring Systems. Is the circuit repair complete? | -- | -- | |
Is the action complete? | -- | -- |
