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MCI SERVICE INFORMATION

D Series Sedan Entrance Door Controls

The operation of the "D" model sedan-style entrance door may appear straightforward, but if you have problems, things become very confusing. Below are a few steps to determine what is not working properly.

Located in the spare tire compartment is the control panel for the entrance door. On this panel are two electrical relays, a stud strip, and assorted valves and pressure switches. Listed below are the functions of the various studs on this stud strip:

Stud 1:	24V power supply whenever the main battery disconnect switch is on.
Stud 2:	24V power supply whenever "door open" switch (interior or exterior) is depressed.
Stud 3:	Ground connection with entrance door opened. Open circuit when interior "door close" switch is depressed.
Stud 4:	Ground connection with entrance door opened. Open circuit when either interior or exterior "door close" switch is depressed.
Stud 5:	24V power supply after "door open" switch (interior or exterior) is pressed. Power remains until "door close" switch is depressed. (This power supply also is used to energize the step light switch).
Stud 6:	Ground connection with entrance door opened.

OPENING THE ENTRANCE DOOR

24V power is supplied to Stud 2 through either the interior or exterior "door open" switch, which energizes the control relay and the latching relay. The control relay when energized removes the power to the skinner valve for the control valve and supplies a temporary ground for the latching relay. The latching relay supplies 24V power to the 4-way valve and also has a diode jumper that keeps the relay "latched" on.

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CLOSING THE ENTRANCE DOOR

While the "door closed" switch is depressed, the ground connection to the latching relay and the skinner valve for the control valve is removed. This de-energizes both the skinner valve and the 4-way valve, allowing the door to close.

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When the "door closed" switch is released, the skinner valve is re-energized stopping the door movement.

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Once the entrance door is closed, there is a microswitch that supplies a ground signal for the door latch solenoid.

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If you need further assistance, contact the MCI Customer Support Center at (800) 241-2947.