Hybrid Vehicles: High Voltage Circuit Disconnect Overview

Hybrid Vehicles: High Voltage Circuit Disconnect Overview Special Thanks to Mr. Tom Melito of Heyward Allen Toyota in Athens, Ga for his help in preparing this lesson written by Whitney Kizer. Whitney Kizer and Dr. Frank B. Flanders Georgia CTAE Resource Network Curriculum Office July 2008

CAUTION!!! These procedures are for GENERAL KNOWLEDGE ONLY! The following steps and procedures are only to be performed by qualified technicians. High Voltage Circuit WHAT?? The high voltage circuit disconnect or SERVICE PLUG on a hybrid vehicle connects the large battery to the rest of the car. Without the

service plug the car could not run. Service plugs are small, plastic pieces the fit into the side of the battery in a hybrid. Service Plug The Service Plug Does What? The service plug connects all the electricity within a hybrid. When you remove the

service plug from the main battery it stops the flow of electricity through the car. The service plug must be removed BEFORE any electrical service can be done on the car. Service plug Main LARGE battery. Location of the Hybrid Vehicle Service Plug

The hybrid vehicle service plug is generally located underneath/behind the BACK SEAT of the car. To complete electrical service on a hybrid vehicle the backseat must be removed to get to the service plug. Use Caution When Servicing Hybrid Batteries and Electrical Systems High-voltage wire

harness connectors are colored ORANGE and also are usually accompanied by High Voltage caution labels. Technicians have to be careful to follow special safety precautions when dealing with hybrid inspections and servicing. Electrical circuitry within a hybrid engine.

Safety Precautions Continued Technicians should wear insulated gloves and remove the service plug to prevent ELECTROCUTION. Technicians should carry the service plug in your pocket to prevent other technicians reinstalling the service plug while work is being done on the hybrid vehicle.

Servicing Safety Continued After removing the service plug, wait 5 minutes prior to beginning work to discharge the high-voltage condenser inside the inverter. Use CAUTION: HIGH VOLTAGE. DO NOT TOUCH DURING OPERATION signs to notify other technicians of service being conducted on the hybrid vehicle. Gasoline

Engine Electric Motor General Safety Procedures Before wearing insulated gloves, check to make sure they are not cracked or have holes or are damaged in any other way. Do not carry metal objects when servicing the vehicle. Dropping these items could cause a SHORT

CIRCUIT within the vehicle. Lets Review The high-voltage service plug helps CONNECT the electrical components of a hybrid vehicle. The safety plug is a component of the BATTERY. SAFETY is of the utmost importance when servicing a hybrid vehicle.

INSULATED GLOVES should be used to protect the technician from being ELECTROCUTED. Hybrid electrical components are easily distinguished from other wiring because they have ORANGE WIRES. That, That, That, Thats All Folks!!!