Audiovox IMO-720 User Manual

Model IMO-720

Installation Manual

IMO-720 Two Circuit Immobilizer System

Kit Contents:

Control Module
5 Pin Main Control Module Wiring Harness
4 Pin High Current Inhibit Circuit Wiring Harness
Valet/Override Switch/LED Combination Assembly
2 Pin Exciter Coil
Consumer Transponder/Information Kit

Operation:

The IMO-720 Immobilizer is a passive arming security system. When the ignition switch is turned off, the LED
begins to flash rapidly, indicating that the circuit will arm in 15 seconds.

After the 15 second arming period, the LED will begin it’s slow flash pattern, indicating that the circuit is armed.

NOTE: The arming cycle can be suspended anytime during the initial 15 seconds by turning the ignition switch

to the on position.

Once the circuit has armed, the vehicle will not start unless a programmed transponder is used or, the manual
override sequence is operated.

When the vehicle door is opened, or when the ignition switch is turned to the on position, the exciter coil is
energized and capable of reading a programmed transponder.

When a transponder is placed within the exciter coil’s field, (Appx. 6”), the unit disarms. This is indicated by the
LED turning off.

Because the programmed transponder is attached the vehicle’s key ring, the operation of this unit is transparent
to the user. Arming and Disarming takes place automatically.

Control Module Mounting:

Select an inconspicuous mounting location below the driver’s side dashboard that is within 30 inches of the
ignition key cylinder. Be certain your chosen location is away from the vehicle’s steering shaft, (column), to
prevent interference with the proper operation and control of the vehicle. Secure the module to a existing brace or,
wiring harness using cable ties.

Mounting The Valet/Override Switch/LED Assembly:

Select a mounting location within the drivers area that is accessible to the operator of the vehicle and
clearly visible from the outside of the vehicle’s front left and right windows. This switch does not have to be
hidden as the system cannot be disarmed unless the pre-programmed transponder is used or the custom
override code sequence is operated.

Mounting The Exciter Coil:

The loop exciter/antenna coil is designed to be placed around the vehicle’s ignition key cylinder. In certain
vehicles it will be necessary to remove the shroud surrounding the steering column, in other vehicles it may be
necessary to remove the cylinder from the dash panel. The information below references both these applications.

Vehicles with steering column ignition cylinders:

Remove the upper and lower half of the steering column shroud to gain access to the ignition key cylinder. Place
the loop coil around the ignition cylinder. Route the twisted pair of Black and Black w/White stripe wires toward
the control module.

Replace the upper and lower halves of the steering column shroud using care not to pinch the wire’s of the routed
exciter coil harness.

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Vehicles with dash mounted ignition switches:

Remove the lower dash panel to gain access to the ignition key cylinder. Carefully remove the ignition key
cylinder from it’s dashboard mounting. Place the loop coil over the ignition cylinder and reinstall the ignition key
cylinder into it’s dashboard mounting location. Route the twisted pair of wires, Black and Black w/White stripe
toward the control module. In some cases it may be difficult to remove the cylinder from it’s mounting location,
in other cases, by placing the coil and reinstalling the cylinder, the coil will be crushed. For these applications,
it is possible to place the loop coil along side the ignition cylinder from behind the dash panel. It is extremely
important that you mount the loop coil as near to the key cylinder as possible to assure operation. Please review
the loop coil field and transponder relationship diagrams shown right side of the diagram below.

Wiring The Control Module:

5 Pin Main Wiring Harness:

1 Red Wire: + 12 Volt Supply:

This is the constant on battery source for the control circuit. This wire is to be connected to a constant + 12 volt
source using the 5 amp fuse provided. This wire will be connected last after wiring all other components. Do not
connect this wire until instructed later under the heading “Final Connections”.

2 Black Wire: Chassis Ground:

This is the ground source for the control circuit. Connect this wire to a known ground source or to a clean non painted
metal section of the vehicle chassis. NOTE: Be certain to remove any paint to insure a proper ground is made.

3 Yellow Wire: Ignition Input:

This is the ignition input wire for the control circuit. This wire also controls operation of the on board relays.
When the circuit is armed and this wire has +12 volts, the on board relays do not energize thereby, interrupt the
flow of current to the inhibit circuit (s) they are connected to. This wire must be connected to a source that has
+ 12 volts when the ignition switch is turned to the run and start positions and must have 0 volts when the ignition
switch is in the off position. This wire also wakes up the exciter coil to allow the transponder to receive and
transmit information to the control circuit’s arming and disarming functions.

NOTE: This immobilizer utilizes a normally open relay configuration. Be certain that the #1 + 12 Volt, #2 Chassis

Ground, #3 Ignition Control wires are securely connected to their proper location to insure vehicle operation.

4 Brown Wire: Negative Door Input:

This is the negative door input control wire, which wakes up the exciter coil, in negative pin switched door
applications. Typically General Motor, and some Imports vehicles use negative switched door pin switch circuits.
Connect this wire to the wire that switches to ground when the drivers door is opened.

5 Purple Wire: Positive Door Input:

This is the positive door input control wire, which wakes up the exciter coil, in positive pin switched door applications.
Typically Ford, Lincoln, and Mercury, and some Imports vehicles use positive switched door pin switch circuits.
Connect this wire to the wire that switches to positive 12 volts when the drivers door is opened.

NOTE: Wire #4, negative door input, or wire #5, positive door input, along with wire #3, ignition input, are used to

wake up the exciter coil enabling the transponder to receive and transmit information to the control

circuit. In addition, these wires are used during the transponder programming sequence. It is imperative

that one of these wires #4 or #5 be used in all applications dependent on the door pin’s switching polarity .

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