Climate Controlled Seat System: Notes

WARNING: This page is about a different car, the 2012 Ford Pickup. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Avoid applying voltage directly to a Thermo-Electric Device (TED) for testing its operation. Doing so may cause damage to the TED.

NOTE: When installing a new Dual Climate Controlled Seat Module (DCSM), it is necessary to carry out Programmable Module Installation (PMI). REFER to MODULE CONFIGURATION .

Both the driver and front passenger climate controlled seats are independently controlled electronically by the DCSM mounted to the bottom of the passenger seat cushion. The climate controlled seat system only operates with the engine running. However, if a scan tool is used to command the DCSM, diagnostic testing can be carried out with the ignition ON engine OFF in 15 second durations.

If one of the voltage supply circuits opens, both seats will remain operational because the circuits are connected internally in the DCSM.

If a fault occurs and sets a DTC specific to either climate controlled seat, only the affected seat is disabled by the module. If the system shuts down due to a DTC fault, cycling the ignition to OFF and then ON again resets the DCSM to function until the DTC sets again.

The 4 climate controlled seat switches (identified with seat icons) on the HVAC module activate each seat system setting and illuminate indicators above each switch to indicate the operating mode. Each switch uses 3 indicators for HIGH, 2 indicators for MED and 1 indicator for LOW.

Each driver and front passenger seat cushion and backrest is equipped with a Thermo-Electric Device (TED) and blower motor assembly. Applying voltage to the TED in one direction causes it to heat. Applying voltage polarity in the opposite direction causes the TED to cool. 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 incoming air depending on the control switch settings. 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 activated, the DCSM maintains the heating/cooling modes until deactivated.

The temperature differences between the individual heated and cooled settings is minimal. For example, it is difficult to distinguish between LOW cool and MED cool settings. Measuring seat temperature at different settings is possible by monitoring the DCSM PIDs using the scan tool.

The HVAC module communicates climate controlled seat commands to the DCSM using the Medium Speed Controller Area Network (MS-CAN) bus. The MS-CAN bus is connected to the Data Link Connector (DLC) for diagnostic use. No direct connection exists between the DCSM and HVAC module for the climate controlled seat switches. The climate controlled seats can be commanded on or off using the scan tool to verify both module communication on the MS-CAN bus and operation of the DCSM. This method can be useful for isolating a control switch concern. REFER to MODULE COMMUNICATIONS NETWORK for information concerning CAN bus communication.