Medium Duty Operator's Manual - Peterbilt Motors Company

Electrical System
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.
Jump Starting Vehicles
Preventive Maintenance
Because of the various battery installations and optional
electrical systems, Peterbilt does not recommend that you
attempt to jump start your vehicle. If you have a battery problem,
it is best to contact a Peterbilt Dealer or a reputable towing
service.
However, if your battery is discharged (dead), you may be
able to start it by using energy from a good battery in another
vehicle. This is termed “jump starting.” Be sure to follow the
precautions and instructions below.
WARNING! Batteries contain acid that can burn
and gases that can explode. Ignoring safety procedures
can cause you or others to be badly
hurt.
WARNING! Never jump start a battery near fire,
flames, or electrical sparks. Batteries generate
explosive gases that could explode causing
serious personal injury. Keep sparks, flame, and
lighted cigarettes away from batteries.
– 216 – Y53-6008A Medium Duty (R05/09)