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the heated seat is turned off, and the rear door module removes the battery voltage from the low temperature indicator.
Load Management Three levels of load management are controlled by the DIM. The DIM sends the status of the load management to the RIM via a Class 2 message. The ON/OFF status of the heated seats is reported to the RIM through the status-signal circuit of each heated seat module. The RIM inhibits the heated seat function for the heated seats through the heated seat module inhibit-signal circuit, according to the level of load management. During load shed level 00, the RIM leaves the heated seat inhibit-signal circuit open so that each heated seat module is in the normal mode of operation. During load shed level 01, the RIM will cycle the signal from High to Low every 0.25 second to set the heat level to the low setting. During load shed level 02, the RIM will supply a constant ground through the heated seat module inhibitsignal circuit to the heated seat modules. In response to this signal, the heated seat module then removes the battery voltage from the seat heating elements. The instrument cluster will display a Battery Saver Active message.
Chapter Fifteen
switches mounted near the driver. Door-jamb switches usually control seat-back latches. In some GM door lock systems, current flows through a solenoid winding to ground (Figure 15-31) when the driver closes the switch. The solenoid core movement either locks or unlocks the door, depending upon which switch position is selected. Some Ford and Chrysler electric door locks use a relaycontrolled circuit as shown in Figure 15-32. Current from the control switch flows through the relay coil, closing the relay contacts. The contacts route current directly from the fuse panel to the solenoid windings. Other Ford, Chrysler, and GM power door locks use an electric motor to move the locking mechanism. The electric motor receives current through a relay (Figure 15-32) Power trunk latches use an insulated switch and a grounded solenoid coil (Figure 15-33). Power seat-back releases can be automatically controlled by grounding door-jamb switches (Figure 15-34). Opening one of the front doors energizes a relay; the relay contacts conduct current to solenoids, which unlatch both seat backs.
POWER DOOR LOCKS, TRUNK LATCHES, AND SEATBACK RELEASES Solenoids and motors are used to control door, trunk, and seat-back latches, and locks. Door and trunk systems are usually controlled by separate
Figure 15-31. GM power door lock system. (GM Service and Parts Operations)
Figure 15-32. DaimlerChrysler power door lock system. (DaimlerChrysler Corporation)
