VIGIL® General Information

General Description

The VIGIL system consists of a lightbar located above the speedometer and tachometer, along with necessary wiring circuits. There are three models: VIGIL I, VIGIL II, and VIGIL III.

VIGIL I: Activates warning lights and/or a buzzer for impending engine or brake failures but does not shut down the engine.

VIGIL II: Activates warning lights and a buzzer for impending failures and shuts down the engine by stopping fuel flow if the condition worsens. Older models may have DIP switches to disable the automatic engine shutdown feature, allowing it to function as a warning system only.

VIGIL III: Includes all VIGIL II features plus an automatic starter lockout to prevent starter overheating and engagement with a running engine. It also features a road speed governor to limit vehicle speed and an overspeed indicator light.

The overspeed indicator light serves two purposes: it signals a malfunctioning speedometer sensor or road speed governor, or indicates when the vehicle exceeds a preset speed. If the vehicle exceeds the governed speed for two minutes, or the engine runs at 1700 RPM for 15 minutes without a speedometer reading, the light illuminates and remains on until the engine is shut down. It will flash for ten seconds each time the engine is started until cleared. The light should only be cleared after the road speed governor and speedometer sensor are checked and repaired.

The engine shutdown feature on VIGIL II and III has an automatic override allowing the engine to run for approximately 30 seconds after shutdown if the vehicle needs to be moved to a safe location.

VIGIL III also provides six outputs for transmitting vehicle speed information from the transmission-mounted magnetic sensor to devices like the speedometer, odometer, trip recorders, fuel economy gauge, or satellite navigation devices.

All models include the following functions:

• Turn Signal Indicators
• High Beam Indicator
• Low Oil Pressure Warning
• Low Air Pressure Warning
• Low Coolant Level Warning
• High Coolant Temperature Warning

Optional features may include indicator lights for:

• Transmission Temperature
• Fifth Wheel Lock
• Utility Light
• Sludge Ejector
• Alternator No Charge
• Engine Heater
• Mirror Heater
• Sand
• Axle Temperature
• Parking Brake
• Cruise Control
• PTO

Note: Except for high beam and turn signal indicators, other lightbar lights do not stay on when the ignition is switched off. Operators should ensure non-ignition-controlled options like heated mirrors and utility lights are manually shut off.

Identification

To identify the VIGIL system in a vehicle:

1. Turn on the key. If the low air and low oil pressure warning lights and buzzer activate until system pressures build, it is VIGIL I.
2. If the lights and buzzer activate in two one-second pulses (a self-check), it is VIGIL II or III. The low air and oil pressure lights remain on. If the lightbar includes lights for starter lockout or road speed governor, it is VIGIL III; otherwise, it is VIGIL II.
3. If a heavy frame surrounds the lightbar face and the warning buzzer does not sound until the starter button is pressed, it may be a Kysor VIP system.

Principles of Operation

The VIGIL system's warning lights and buzzer are activated by switches controlling floating-activated, ground-activated, or power-activated circuits.

• Floating-activated circuits (e.g., air pressure): Switches are normally open. During operation, air pressure holds them closed. If pressure drops, switches open, the circuit loses ground, and the warning activates.
• Ground-activated and power-activated circuits: Switches are normally closed. They open in response to operating conditions, either grounding the circuit or connecting to a 12-volt source, which activates the warning.

Engine Warning and Shutdown Systems

Low Air Pressure Warning: Controlled by two low-air-pressure switches in the primary and secondary air systems. Both switches are held closed by air pressure above 64 psi (440 kPa). If pressure drops, the switch opens, losing ground and activating the warning.

Low Oil Pressure Warning and Shutdown: Uses floating-activated circuits. Oil pressure holds a switch closed, grounding the circuit. If oil pressure drops below a preset level, the switch opens, losing ground and activating the warning. If oil pressure drops further, a separate switch opens, interrupting fuel delivery to the engine.

Coolant Level Warning: A sensor in the radiator grounds a circuit. If the coolant level drops below the sensor, the circuit loses ground, activating the warning. A five-second delay prevents false alarms from coolant sloshing. In VIGIL II/III, engine shutdown occurs if the sensor is exposed for 30 seconds.

Coolant Temperature Warning: In VIGIL I/II, a switch (alarmstat) normally closed opens as coolant temperature exceeds 215°F (101°C), losing ground and activating the warning. For Cummins M11/N14 engines, this threshold is 220°F (104°C). For shutdown, the threshold is 220°F (104°C) or 225°F (107°C) for Cummins engines.

In VIGIL III, a thermistor monitors coolant temperature. If resistance indicates a temperature above a predetermined level, the warning light activates. If the temperature rises further, the engine is shut down.

Road Speed Governor (VIGIL III): Sets the vehicle's maximum speed between 45 and 85 mph (72-137 km/h), configured at the factory. When the maximum speed is reached, a relay activates the governor solenoid, reducing fuel pressure. There is a 2 mph (3 km/h) lag in the system.

Starter Lock Out (VIGIL III)

VIGIL III prevents starter engagement under the following conditions:

• Key switch voltage is greater than 18 volts.
• Key switch voltage is less than 9 volts before the starter button is pressed.
• Starter button pressed within two seconds of a previous start attempt.
• Engine speed exceeds 350 rpm.
• Starter has been cranking for 30 seconds within a one-minute period (a two-minute lockout follows for starter cooling).

The starter lockout warning light illuminates during the two-minute cooling period or when the starter button is pressed within two seconds of a previous attempt.

Turn Signals

The turn signal circuits are integrated with the VIGIL lightbar. When a turn signal is activated, specific wires connect to the turn signal switch, activating the corresponding front and rear turn signals. The lightbar receives a pulsing ground signal, causing the turn signal arrow on the lightbar to illuminate. Battery circuit power allows turn signals and four-way flashers to operate even when the ignition is off.