Main Disconnect Switch
The main disconnect exists as abreak in the ground cable from the main negative battery post of the batterypack to remove the power from the 72V system. This switch will kill power to the cabling in the rear of the vehicle,and in-turn the power to the 12V system on vehicles with the DC drive system. On AC drive equipped vehicles, also removethe fuse from the F5 location to kill power to the 12V system. This is very important to use when performingany kind of service on the vehicle’s electrical system. It is very important to note; however, thatthis does not remove power from the cabling connecting the batteries to eachother. This cabling is always live dueto the nature of a battery.
Isolated Ground/ShockDanger
The vehicle electrical systemoperates with an isolated ground this keeps the chassis free from grounding andis a safety measure taken due to the presence of a high (72V) voltagesystem. This also makes the vehicle amore service safety friendly. Thechassis not being grounded means that even if a metal object (such as a wrench)is placed from a live positive terminal to the chassis there should beno current. This can never be taken forgranted however, there may be some circumstance that this is not true due to aservice issue or state of disassembly due to a service operation. If a ground cable attached to a battery postis connected with the frame then the frame will be grounded and any positivevoltage that comes in contact with the frame will energize it. Extreme caution should always be taken whenworking with the 72V system and always treat the connections as if theyare very dangerous because most of the time they are. Voltage and amperageleakage from the battery pack to the chassis can be tested with a standardvoltage test meter.
System Voltages
There are two main system voltagesoperating in the vehicle. The first isthe 72V system which consists of the main drive power from the batteries to thecontroller and motor. This system isbasically defined by the heavy gauge cabling found throughout the vehicle. This system carries a large supply of powerat 72V and should be treated with great care when servicing or workingaround. Connection tightness andcleanliness in this system are very critical due to the power loadcarried. Loose connections could lead todamage components, loss of system efficiency and even fire and/or shockhazard.
The second main system voltage isthe 12V system which is derived from the 72V system by means of a converterfound attached to the firewall underneath the hood. This system is used to power all theaccessories inside and outside the vehicle such as all lighting, dash displayand most electrical optional components such as the dome light, heater, fan,and the alike. This system is completelyisolated from the 72V system. It shouldbe noted that there is also a 12V system that is powered from the controllerfor the controller operating systems. Thissystem is not isolated from the 72V system. This non-isolated 12V system includes control systems for the controllerfeedback such as the speedometer readout (dash display), motor speed sensor,direction selector switch, park brake switch, regenerative brake switch andsafety switch for the accelerator pedal. Apart from this small subset of the 12V system, the two 72V and 12Vsystems operate completely isolated from each other including their grounds.
Fuses
72 Volt Fuses
All 72 volt rated fuses are locatedin the rear motor compartment of the vehicle.
In most cases, if these fuses failthere is another issue with your vehicle. Problems that cause fuse failure should be diagnosed by a trainedprofessional.
Front Controls Fuse - Thisfuse is for the front controls of the vehicle (Ignition, converter, heater,etc). It is a 30 amp fuse (NON-30).
Main Drive System Fuse () - Themain fuse for the 72 volt D.C. drive system which is rated for 325 amps(ANN-325).
Main drive System Fuse (AC Drive)- The main fuse for the 72 volt A.C. drive system which is rated for 425 amps (-400) is mounted onto the A.C. drive controller.
12 Volt Fuses
The 12 volt fuses are located atthe front of the vehicle beneath the hood. To access them, unlatch and open the hood and remove the aluminum tunnelcover. The fuse panel is a small blackbox in the center. Remove the weathercover by pressing both of the side tabs and lifting upward. The fuse circuit, size and panel locationsare given in the following table:
Fuse Table
Fuse Location | Circuits Protected | Fuse |
F1 | Ignition | 7.5 Amp |
F2 | Hazard & Turn Lights | 10 Amp |
F3 | Radio | 10 Amp |
F4 | Interior Dome Light | 5 Amp |
F5 | 12 Volt Battery (A.C. Drive Only) | 25 Amp |
F6 | Lithium BMS | 5 Amp |
F7 | Fuel Fired Heater | 20 Amp |
F11 | Headlights | 20 Amp |
F12 | Horn, Backup Alarm, Backup Light, Backup Camera | 15 Amp |
F13 | Brake Lights, Wiper Motor, 12-volt Accessory Outlet | 15 Amp |
F14 | Heater Coil, Heater Fan, Radio Ignition | 10 Amp |
F15 | 2 Speed Fan, Beacon Light | 10 Amp |
F17 | Air Conditioner/Heater | 20 Amp |