FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.
Home >> Mercury >> 2011 >> Milan FWD L4-2.5L Hybrid >> Repair and Diagnosis >> Accessories and Optional Equipment >> Antitheft and Alarm Systems >> Testing and Inspection >> Pinpoint Tests >> Anti-Theft - Perimeter >> Pinpoint Test D: The Alarm System Does Not Operate Correctly - The Alarm Does Not Arm/Inhibit From The Luggage Compartment Lid

Pinpoint Test D: The Alarm System Does Not Operate Correctly - The Alarm Does Not Arm/Inhibit From The Luggage Compartment Lid




Anti-Theft

Pinpoint Test D: The Alarm System Does Not Operate Correctly - The Alarm Does Not Arm/Inhibit From The Luggage Compartment Lid

Refer to Wiring Diagram Set 117 (Fusion/Milan/MKZ, Fusion Hybrid, Milan Hybrid, MKZ Hybrid), Remote Keyless Entry and Alarm for schematic and connector information. Diagrams By Number

Normal Operation

The Smart Junction Box (SJB) monitors the luggage compartment lid disarm switch on circuit CRT18 (luggage compartment lid disarm switch sense circuit) for a ground signal. The luggage compartment lid disarm switch is a normally open switch. When the key is turned to the unlock position, the disarm switch completes the circuit to ground on ground circuit GD171 signaling the SJB that an authorized entry to the luggage compartment is occurring. The SJB inhibits the alarm from activating until the luggage compartment lid is closed, then adds the luggage compartment lid to the protected entry points.

- DTC B2108 (Trunk Key Cylinder Switch Failure) - an on-demand DTC that sets when there is a short to ground in the circuit between the luggage compartment lid disarm switch and the SJB, or the luggage compartment lid disarm switch is shorted closed internally.

This pinpoint test is intended to diagnose the following:

- Wiring, terminals or connectors
- Luggage compartment lid disarm switch
- SJB


PINPOINT TEST D: THE ALARM SYSTEM DOES NOT OPERATE CORRECTLY - THE ALARM DOES NOT ARM/INHIBIT FROM THE LUGGAGE COMPARTMENT LID

NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery, Mounting and Cables Battery Disconnect.

-------------------------------------------------
D1 CHECK THE LUGGAGE COMPARTMENT LID DISARM SWITCH

NOTE: The luggage compartment lid disarm switch does not disarm (only inhibits) the perimeter alarm system. Once armed, the perimeter alarm can only be disarmed using the Integrated Keyhead Transmitter (IKT) key, the keyless entry keypad (if equipped), or if a valid Passive Anti-Theft System (PATS) key turns the ignition switch to the ON position.

- Ignition OFF.
- Disconnect: Luggage Compartment Lid Disarm Switch C4320.
- Measure the resistance between the luggage compartment lid disarm switch C4320-1, component side and the luggage compartment lid disarm switch C4320-2, component side while turning the luggage compartment lid lock cylinder to the unlock position, then to the at-rest position.




- Is the resistance less than 5 ohms with the luggage compartment lid lock cylinder in the unlock position and greater than 10,000 ohms with the luggage compartment lid lock cylinder in the at-rest position?

Yes
GO to D2.

No
INSTALL a new luggage compartment lid disarm switch. REFER to Luggage Compartment Lid Lock Cylinder in Handles, Locks, Latches and Entry Systems Service and Repair. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

-------------------------------------------------
D2 CHECK CIRCUIT CRT18 (LUGGAGE COMPARTMENT LID DISARM SWITCH INPUT) FOR AN OPEN OR A SHORT TO GROUND

- Disconnect: SJB C2280c.
- Measure the resistance between the SJB C2280c-22, circuit CRT18 (YE/GY), harness side and the luggage compartment lid disarm switch C4320-1, circuit CRT18 (YE/GY), harness side; and between the SJB C2280c-22, circuit CRT18 (YE/GY), harness side and ground.




- Is the resistance less than 5 ohms between the SJB and the luggage compartment lid disarm switch; and greater than 10,000 ohms between the SJB and ground?

Yes
GO to D3.

No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

-------------------------------------------------
D3 CHECK CIRCUIT GD171 (LUGGAGE COMPARTMENT LID DISARM SWITCH GROUND CIRCUIT) FOR AN OPEN

- Disconnect: Negative Battery Cable.
- Measure the resistance between the luggage compartment lid disarm switch C4320-2, circuit GD171 (BK/GY), harness side and ground.




- Is the resistance less than 5 ohms?

Yes
CONNECT the negative battery cable. GO to D4.

No
REPAIR the circuit. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

-------------------------------------------------
D4 CHECK THE SJB FOR CORRECT OPERATION

- Disconnect all the SJB connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the SJB connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?

Yes
INSTALL a new SJB. REFER to Multifunction Electronic Modules Service and Repair. CYCLE each key to the ON position for a minimum of 6 seconds to PROGRAM the Remote Keyless Entry (RKE) function of the IKT keys. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

-------------------------------------------------

pro multis Credits:Operation CHARM About Operation CHARM