Peterbilt Medium Duty Truck Owner's Manual - Peterbilt Motors

Preventive Maintenance
WARNING! Before attempting any work on the
batteries or electrical system, remove all jewelry.
If metal jewelry or other metal comes in contact
with electrical circuits, a short circuit may occur
causing death, injury or property damage.
Removing and Installing Batteries:
1. Be sure all switches on the vehicle are turned OFF.
2. Disconnect negative ground cable.
3. Disconnect positive cable.
4. Unscrew bolt of holding plate with open end wrench.
To reinstall batteries:
1. Place batteries in vehicle and tighten bolt of holding
plate.
2. Reconnect positive cable.
3. Reconnect negative ground cable.
Battery Care
Electrical System
Regular attention to the charging system will help prolong the
service life of the batteries. Here are some common causes
of battery failure:
Overcharge: this condition results from improper voltage
regulator adjustment. It results in overheating of the battery,
warped plates, and evaporation of electrolyte.
Undercharge: the voltage regulator is malfunctioning or is
improperly adjusted, the drive belt is slipping, or your vehicle
has undergone long periods of standing idle or short distance
driving. These conditions result in battery plates becoming
covered with a hard coating.
Vibration: loose battery hold-downs may cause battery
plate failure.
Short Circuits: these discharge the battery by draining
electricity.
Dirty or Loose Connections: improper connections may
stop the flow of electrical power to and from the battery.
Medium Duty (R05/09) Y53-6027 – 221 –