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B1D5E






B1D5E-13-Power Seat Switch - Circuit Open






For a complete wiring diagram, refer to.

Theory of Operation

The Memory System is made up of the Memory Seat Module (MSMD), Memory Switch, Driver Seat Switch, Tilt/Telescope Switch, multiple Seat Motors which also each contain a hall-effect position sensor, and the Tilt and Telescope Steering Motors, both of which contain a hall-effect position sensor.

When the Driver Seat Switch is used to command seat movement, a signal is sent from the Switch to the MSMD via a mux signal circuit. The MSMD will then command the appropriate Seat Motor or Motors to move the seat in the commanded direction as long as the Driver Seat Switch is held in that direction. When seat movement is commanded, the MSMD also powers the hall-effect position sensor located in each Seat Motor. These hall-effect sensors provide feedback to the MSMD in relation to the seat's position. The Tilt and Telescoping Steering operate in a similar manner, with the Tilt Switch and Telescope Switch sending a signal to the MSMD from the Steering Column Control Module (SCCM) via the Controller Area Network (CAN) bus circuit. The Tilt Motor and Telescope Motor are then commanded by the MSMD based on the Switch input. The Tilt Motor and Telescope Motor also each have a hall-effect position sensor.

The Memory Switch is used to set and recall memory seat and steering positions. When a Memory Switch button is pressed, a signal is sent from the Switch to the Driver Door Module (DDM) via a mux signal circuit. The DDM will then request the MSMD perform the function via the Controller Area Network (CAN) bus circuit. If the SET button on the Memory Switch is pressed, followed by the 1 or 2 button, the MSMD will store the seat and steering position based on the position inputs received from the hall-effect position sensor. If the 1 or 2 button on the Memory Switch is pressed, the MSMD will recall the stored position for that particular selection and return the seat and steering column to the stored position. Memory position may also be recalled using a linked FOBIK transmitter. For driver safety, the MSMD will prevent the memory recall function from being initiated if the transmission gear selector lever is not in the Park position or if the vehicle is moving.

When Monitored: Continuously.

Set Condition: The MSMD detects an open in either driver seat switch mux circuit.






Test Step 1 - TEST FOR INTERMITTENT CONDITION

Turn the ignition on.

With the scan tool, record and erase DTCs

Cycle the Driver Seat Switch in all directions several times.

Wait one minute.

With the scan tool, read the active DTCs.

Does the scan tool display B1D5E-13-POWER SEAT SWITCH - CIRCUIT OPEN?

Yes

Go to Test Step 2 => [ Test Step 2 - CHECKING THE (P28) DRIVER SEAT SWITCH MUX RETURN CIRCUIT ]

No

Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

Test Step 2 - CHECKING THE (P28) DRIVER SEAT SWITCH MUX RETURN CIRCUIT







Turn the ignition off.

Disconnect the Driver Seat Switch harness connector.

Measure the resistance between ground and the (P28) Driver Seat Switch Mux Return circuit.

Is the resistance below 40 Ohms?

Yes

Go to Test Step 3 => [ Test Step 3 - CHECKING THE (P311) DRIVER SEAT FRONT VERTICAL/RECLINER
SWITCH MUX CIRCUIT ]

No

Go to Test Step 5 => [ Test Step 5 - CHECKING THE (P28) DRIVER SEAT SWITCH MUX RETURN CIRCUIT
FOR AN OPEN OR EXCESSIVE RESISTANCE ]

Test Step 3 - CHECKING THE (P311) DRIVER SEAT FRONT VERTICAL/RECLINER SWITCH MUX CIRCUIT







Connect the Driver Seat Switch harness connector.

Disconnect the MSMD C4 harness connector.

Measure the resistance between the (P311) Driver Seat Front Vertical/Recliner Switch Mux circuit and the (P28) Driver Seat Switch Mux Return circuit.

Is the resistance between 40 and 60 Ohms?

Yes

Go to Test Step 4 => [ Test Step 4 - CHECKING THE (P309) DRIVER SEAT REAR VERTICAL/HORIZONTAL
SWITCH MUX CIRCUIT ]

No

Go to Test Step 6 => [ Test Step 6 - CHECKING THE (P311) DRIVER SEAT FRONT VERTICAL/RECLINER
SWITCH MUX CIRCUIT FOR AN OPEN OR EXCESSIVE RESISTANCE ]

Test Step 4 - CHECKING THE (P309) DRIVER SEAT REAR VERTICAL/HORIZONTAL SWITCH MUX CIRCUIT







Measure the resistance between the (P309) Driver Seat Rear Vertical/Horizontal Switch Mux circuit and the (P28) Driver Seat Switch Mux Return circuit.

Is the resistance between 40 and 60 Ohms?

Yes

Go to Test Step 8 => [ Test Step 8 - MEMORY SEAT MODULE (MSMD) ]

No

Go to Test Step 7 => [ Test Step 7 - CHECKING THE (P309) DRIVER SEAT REAR VERTICAL/HORIZONTAL
SWITCH MUX CIRCUIT FOR AN OPEN OR EXCESSIVE RESISTANCE ]

Test Step 5 - CHECKING THE (P28) DRIVER SEAT SWITCH MUX RETURN CIRCUIT FOR AN OPEN OR EXCESSIVE RESISTANCE







Disconnect the MSMD C4 harness connector.

Measure the resistance of the (P28) Driver Seat Switch Mux Return circuit between the Driver Seat Switch harness connector and the MSMD harness connector.

Is the resistance above 10 Ohms?

Yes

Repair the open or excessive resistance in the (P28) Driver Seat Switch Mux Return circuit.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

No

Go to Test Step 8 => [ Test Step 8 - MEMORY SEAT MODULE (MSMD) ]

Test Step 6 - CHECKING THE (P311) DRIVER SEAT FRONT VERTICAL/RECLINER SWITCH MUX CIRCUIT FOR AN OPEN OR EXCESSIVE RESISTANCE







Disconnect the Driver Seat Switch harness connector.

Measure the resistance of the (P311) Driver Seat Front Vertical/Recliner Switch Mux circuit between the Driver Seat Switch harness connector and the MSMD harness connector.

Is the resistance above 10 Ohms.

Yes

Repair the open or excessive resistance in the (P311) Driver Seat Front Vertical/Recliner Switch Mux circuit.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

No

Replace the Driver Seat Switch.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

Test Step 7 - CHECKING THE (P309) DRIVER SEAT REAR VERTICAL/HORIZONTAL SWITCH MUX CIRCUIT FOR AN OPEN OR EXCESSIVE RESISTANCE







Disconnect the Driver Seat Switch harness connector.

Measure the resistance of the (P309) Driver Seat Rear Vertical/Horizontal Switch Mux circuit between the Driver Seat Switch harness connector and the MSMD harness connector.

Is the resistance above 10 Ohms.

Yes

Repair the open or excessive resistance in the (P309) Driver Seat Rear Vertical/Horizontal Switch Mux circuit.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

No

Replace the Driver Seat Switch.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

Test Step 8 - MEMORY SEAT MODULE (MSMD)

Using the wiring diagram/schematic as a guide, inspect the wiring and harness connectors between the Driver Seat Switch and the MSMD.

Look for any chafed, pierced, pinched, or partially broken wires.

Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Driver Seat Switch and MSMD harness connectors.

Perform any Technical Service Bulletins that may apply.

Were there any problems found?

Yes

Repair as necessary.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test

No

Replace the MSMD.

Perform Power Seat System Verification Test. Refer to => Non - DTC Based Diagnostics. Power Seat System Verification Test