B210D-21

B210D-21-BATTERY VOLTAGE LOW - SIGNAL AMPLITUDE < MINIMUM

For a complete wiring diagram, refer to the Wiring Information.





Theory of Operation

The Memory System is made up of the Memory Seat Module-Driver (MSMD), Memory Switch, Driver Seat Switch, Adjustable Pedal Switch, and multiple Seat Motors and an Adjustable Pedal Motor. The motors each contain a hall-effect position sensor. The hall-effect position sensor provides feedback to the MSMD in relation to the motors position.

The Driver Seat Switch is a Multiplex (Mux) switch which uses set resistance levels for each switch position. These resistances correspond to different voltages which is monitored by the MSMD over two separate circuits. When a voltage change is detected, the MSMD will command the appropriate Seat motor(s) to move the seat in the requested direction as long as the Driver Seat Switch is held in that direction or its stops have been reached.

The Adjustable Pedal Switch is a three position switch (forward, center, rearward). The MSMD monitors the forward and rearward circuits voltage. If a voltage change is detected, the MSMD will command the Adjustable Pedal motor to move the pedals in the requested direction as long as the Adjustable Pedal Switch is held in that direction or its stops have been reached.

The Memory Switch is a Mux switch that is used to set and recall the seat and pedal positions. When a Memory Switch button is pressed, the Driver Door Module (DDM) detects a voltage change and sends a request over the Controller Area Network (CAN) bus circuit to the MSMD to perform the requested command. If the SET button on the Memory Switch is pressed, followed by the 1 or 2 button, the MSMD will store the seat and pedal positions based on the position inputs received from the hall-effect position sensors. If the 1 or 2 button on the Memory Switch is pressed, the MSMD will recall the stored seat and pedal positions for that particular selection and return the seat and pedals to the stored positions. 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. For further information Memory Seat Module - Operation.

- When Monitored:
Engine running, during seat motor operation.

- Set Condition:
The Memory Seat Module-Driver (MSMD) detects a voltage under 9.5 volts on the Fused B(+) circuit.





Diagnostic Test

1. CHECK PCM FOR CHARGING SYSTEM DTC
1. With the scan tool, read the PCM DTCs.

Are there any Charging System DTCs set in the PCM?

Yes

- Testing and Inspection and perform the appropriate diagnostic procedure.

No

- Go To 2

2. CHECK IF THE DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, record and erase Memory Seat Module-Driver (MSMD) DTCs.
3. Cycle the ignition switch from off to on.
4. Start the engine and operate the driver power seat.
5. With the scan tool, read MSMD DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 3

No

- 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 the POWER SEAT SYSTEM VERIFICATION TEST. Verification Tests.

3. CHECK THE (A942) FUSED B(+) CIRCUIT FOR AN OPEN OR HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the MSMD C1 harness connector.
3. Ignition on, engine running.
4. Using a 12-volt test light connected to ground, check the (A942) Fused B(+) circuit in the MSMD C1 harness connector.

NOTE: The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.

Does the test light illuminate brightly?

Yes

- Replace and program the Memory Seat Module (MSMD). Memory Seat Module - Removal.
- Perform the POWER SEAT SYSTEM VERIFICATION TEST. Verification Tests.

No

- Repair the (A942) Fused B(+) circuit for an open or excessive resistance.
- Perform the POWER SEAT SYSTEM VERIFICATION TEST. Verification Tests.