Pinpoint Test Aw : DTC B272F: Notes

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: This DTC sets for an open or short to voltage. See DTC setting description below.

Refer to Climate Controlled Seats , for schematic and connector information.

Normal Operation

Both the driver and front passenger climate controlled seats are independently controlled electronically by the Front Seat Climate Control Module (SCME) mounted to the bottom of the passenger seat cushion. The climate controlled seat system only operates with the engine running, however, if using a scan tool to command the Front Seat Climate Control Module (SCME), diagnostic testing can be carried out with the ignition ON engine OFF. The system receives voltage from BJB fuse 67 (40A) feeding battery voltage on circuit SBB67 (BU/RD) into Front Seat Climate Control Module (SCME) C3265A pins E and F. If voltage is disconnected from either pin E or F of Front Seat Climate Control Module (SCME) C3265A with the voltage connection remaining on the other circuit, both seats will remain operational because the voltage feed circuits are connected internally in the Front Seat Climate Control Module (SCME). However, if a fault occurs setting a DTC specific to either climate controlled seat, only the affected seat will be disabled by the module.

Each driver and front passenger seat cushion is equipped with a TED assembly that includes a seat blower (fan motor, serviced as an assembly with the TED). Similarly, each driver and front passenger seat backrest is also equipped with its own TED assembly with blower. Cabin air is drawn through the blower and distributed to each of the TED modules located in the seat cushion and backrest. The TEDs then heat or cool the air. The air is then directed into the foam pad and manifold where it is distributed along the surface of the cushion and backrest of the seat. Once the system is activated, the Front Seat Climate Control Module (SCME) uses a set of flexible algorithms to control the heating/cooling modes and the blower speed dependant on the climate controlled seat switch settings.

DTC B272F (Passenger Ignition Run/Blower Circuit Short to Ground) - This DTC is set if the blower voltage or ground circuit opens to both backrest and cushion blowers or if both blower voltage circuits short to voltage. Only one blower voltage circuit needs to be open for the DTC to be set if battery voltage is less than 12 volts.

This pinpoint test is intended to diagnose the following:

Wiring, terminals or connectors
Backrest or cushion TED
Front Seat Climate Control Module (SCME)