Front Seats — 2016 workshop reference 1092

The SCME monitors seat cushion temperature while it supplies voltage and ground to both blower motors. The SCME also supplies a variable voltage signal to control the blower speed. Cabin air enters the blower through a filter attached to the blower motor housing. Heated or cooled air exits the blower motor and flows through a duct to the foam pad.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Conditions
	B2729 Cushion Over-Temp Detected	If the driver seat cushion blower motor temperature exceeds 70° C (158° F) in cool mode or 85° C (185° F) in heat mode for more than 4 seconds, the SCME shuts down the driver seat system and sets this DTC.

DTC

Description

Fault Trigger Conditions

B2729 Cushion Over-Temp

Detected

If the driver seat cushion blower motor temperature exceeds 70° C (158° F) in cool mode or 85° C (185° F) in heat mode for more than 4 seconds, the SCME shuts down the driver seat system and sets this DTC.

Possible Causes

Wiring, terminals or connectors Restricted blower motor filter Crushed or restricted cushion foam pad Cushion blower motor SCME

PINPOINT TEST AF : DTC B2729

WARNING: Incorrect repair techniques or actions can cause an accidental Supplemental Restraint System (SRS) deployment. Never compromise or depart from these instructions. Failure to precisely follow all instructions could result in serious personal injury from an accidental deployment.

AF1 CHECK THE SCME (FRONT SEAT CLIMATE CONTROL MODULE) FOR ON-DEMAND DIAGNOSTIC TROUBLE CODES (DTCS)

Start the vehicle and set the driver seat to HIGH heat. Using a diagnostic scan tool, perform the SCME self-test.

Was DTC B2729 retrieved on-demand during the self-test?

Yes	GO to AF2
No	GO to AF5

AF2 CHECK THE DRIVER SEAT CUSHION BLOWER MOTOR THERMISTOR CIRCUITS FOR A SHORT TO GROUND

REFER to: Supplemental Restraint System (SRS) Depowering (501-20B Supplemental Restraint System, General Procedures). Disconnect: Driver Side Airbag In-line C345. Disconnect: Passenger Side Airbag In-line C219. Disconnect: SCME C3265B. Disconnect: Driver Seat Cushion Blower Motor C3035. Measure:

Click to display connectors

Positive Lead	Measurement / Action	Negative Lead
C3265B-7		Ground
C3265B-8		Ground

Are the resistances greater than 10,000 ohms?

Yes	GO to AF3
No	REPAIR the circuit in question. GO to AF22

AF3 CHECK THE DRIVER SEAT CUSHION BLOWER MOTOR THERMISTOR AND WIRING

Connect: Driver Seat Cushion Blower Motor C3035. Measure:

Click to display connectors

Positive Lead	Measurement / Action	Negative Lead
C3265B-7		C3265B-8

Compare the measured resistance value with the following table:

Ambient Temperature	Resistance
0-10° C (32-50° F)	2,782-1,663 ohms
10-20° C (50-68° F)	1,837-1,140 ohms
20-30° C (68-86° F)	1,260-806 ohms
30-40° C (86-104° F)	893-570 ohms

Source reference 1092

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.