Chapter 29 POWERPOINT

Use the textbook to define these Technical Terms:

1. battery charger-

2. battery drain test

3. battery load test

4. battery terminal test

5. battery voltage test

6. hydrometer

7. parasitic load (parasitic draw)

Use the textbook to answer these discussion questions:

1. List the obvious problems to look for when visually inspecting a 12-volt battery.

2. List the common tests on 12-volt batteries.

Read the chapter summary below:

Summary

■ 12-volt battery maintenance tasks should be performed regularly to ensure optimal service life.

■ A battery leakage test will find out if current is discharging across the top of the battery case.

■ A battery terminal test quickly checks for a poor electrical connection between the battery cables and terminals.

■ Clean battery terminals and coat with a conductive, dielectric compound or white grease before reinstalling the battery cables.

■ When measuring battery charge, you are checking the condition of the battery electrolyte and battery plates.

■ A parasitic load is any electric circuit current draw present when the engine and all electrical devices are shut off.

■ A battery charger forces current back through the battery to restore the charge on the cell plates.

■ A battery load test actually measures the current and voltage output and overall performance of the battery cells.

■ A fully charged battery should have an OCV (no- load, open circuit voltage) of 12.4 volts or higher.

■ HV battery service life averages about 150,000 miles.

■ Full hybrids or full-electric vehicles cannot be jumped and must be towed to a service facility if they have a dead or discharged HV battery.

■ Use a scan tool and the combination meter in the dash display to evaluate HV battery condition.

■ HV battery state-of-charge should be at least 80% of maximum voltage rating after a full recharge.

■ An HV battery load test drive measures current and voltage levels into and out of the large battery pack while driving or during simulated driving.

■ The most common reasons for HV battery replacement are age and physical damage.

■ When removing an HV battery, refer to factory service information showing battery location, electrical connections, and mounting.

■ A poor HV power cable connection can cause cable overheating, reduced current flow, lowered motor-generator torque, and overall reduced electrical efficiency.