AB35 CHECK THE SCME (FRONT SEAT CLIMATE CONTROL MODULE) OPERATION
corrosion (install new connector or terminals - clean module pins) damaged or bent pins - install new terminals/pins as necessary pushed-out pins - install new pins as necessary
Reconnect the SCME connectors. Make sure they seat and latch correctly.
NOTE: Do not reconnect Driver Side Airbag In-line C345 or Passenger Side Airbag In-line C219 at this time. Reconnect all previously disconnected connectors. Ignition ON. Operate the system and determine if the concern is still present.
Is the concern still present?
Yes | CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new SCME. REFER to: Front Seat Climate Control Module [SCME] (501-10A Front Seats, Removal and Installation). GO to AB36 |
|---|---|
No | The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues. GO to AB36 |
AB36 VERIFY THE SUPPLEMENTAL RESTRAINT SYSTEM (SRS) PROVES OUT SUCCESSFULLY
REFER to: Supplemental Restraint System (SRS) Depowering (501-20B Supplemental Restraint System, General Procedures). Connect: Driver Side Airbag In-line C345. Connect: Passenger Side Airbag In-line C219. Connect all previously disconnected connectors.
REFER to: Supplemental Restraint System (SRS) Repowering (501-20B Supplemental Restraint System, General Procedures).
Did the SRS prove out successfully?
Yes | Repair is complete. RETURN the vehicle to the customer. |
|---|---|
No | REFER to: Airbag Supplemental Restraint System (SRS) (501-20B Supplemental Restraint System, Diagnosis and Testing). |
DTC B272D
Refer to Wiring Diagrams Cell 119 for schematic and connector information.
Normal Operation and Fault Conditions
The SCME is supplied voltage at all times, but the climate controlled seat system only operates with the engine running. The system can be operated with the ignition ON engine OFF by using a diagnostic scan tool to bypass the climate controlled seat buttons on the touchscreen and FCIM. When commanding a heat or cool mode operation in this manner, the climate controlled seat system only operates in 15 second intervals.
Both voltage supply circuits are spliced together internal to the SCME, so if one circuit becomes open, both seats can still be operated. However, if a fault occurs setting a DTC specific to either climate controlled seat, only the affected seat is disabled by the SCME.
Cabin air is drawn through and distributed to each of the blower motors located in the seat cushion and backrest. The blower motors then heat or cool the air. The air is then directed into the foam pad where it is distributed along the surface of the cushion and backrest of the seat. Once the system is activated, the SCME uses a set of flexible algorithms to control the heating/cooling modes and the blower speed dependant on the commanded climate controlled seat settings.
A differential fault occurs when the cushion and backrest blower motors on an affected seat are reporting very different temperatures to the SCME. This may result from an airflow restriction or a circuit fault of either blower motor area. If a blower motor is clear of obstruction and is operational, check the other blower motor and circuitry on the seat. It is important to note that a blower motor with a higher temperature may be operating correctly and not the area of concern. The other blower motor may be indicating a much lower temperature, causing the DTC to set.
DTC Fault Trigger Conditions
DTC | Description | Fault Trigger Conditions |
|---|---|---|
B272D Passenger Differential Temperature Fault | If there is a temperature differential between the passenger backrest and cushion blower motor of 60° C (108° F) or more for more than 4 seconds, or if the blower motor is disconnected or the duct is blocked, this DTC sets. When this happens for the first time in a key cycle, the SCME puts the passenger seat system into recovery mode (see principles of operation). If the system is able to recover, it returns to normal function. If the system is able to recover and it occurs a second time in the same key cycle, the SCME shuts down the passenger seat system. |
2016 Mustang workshop publication supplied to Mustang Atlas. Original technical text and illustrations; HTML formatting by Mustang Atlas. Source page numbering is retained for traceability. Follow the configuration, revision, warnings, and cross-references in the material. About this edition.