Starting System

STARTING SYSTEM

Starting System Diagnosis:

The battery, starting, and charging systems operate in conjunction with one another, and must be tested as a complete system. For correct starting/charging system operation, all of the components involved in these 3 systems must perform within specifications.

INSPECTION
For complete starter wiring circuit diagrams, refer to Wiring Diagrams. Before removing any unit from starting system for repair or diagnosis, perform the following inspections:

WARNING: ON VEHICLES EQUIPPED WITH AIRBAGS, REFER TO PASSIVE RESTRAINT SYSTEMS, BEFORE ATTEMPTING ANY STEERING WHEEL, STEERING COLUMN, OR INSTRUMENT PANEL COMPONENT DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE PROPER PRECAUTIONS COULD RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT AND POSSIBLE PERSONAL INJURY.

- Battery - Visually inspect battery for indications of physical damage and loose or corroded cable connections. Determine state-of-charge and cranking capacity of battery. Charge or replace battery if required. Refer to Battery in Battery. NOTE: If equipped with diesel engine, a dual battery system may be used, and both batteries must be inspected.
- Ignition Switch - Visually inspect ignition switch for indications of physical damage and loose or corroded wire harness connections. Refer to Ignition Switch and Key Lock Cylinder.
- Park/Neutral Position Switch - Visually inspect park/neutral position switch for indications of physical damage and loose or corroded wire harness connections. Refer to Park/Neutral Position Switch, Transmission.
- Starter Relay - Visually inspect starter relay for indications of physical damage and loose or corroded wire harness connections.
- Starter Motor - Visually inspect starter motor for indications of physical damage and loose or corroded wire harness connections.
- Starter Solenoid - Visually inspect starter solenoid for indications of physical damage and loose or corroded wire harness connections.
- Wiring - Visually inspect wire harnesses for damage. Repair or replace any faulty wiring, as required. Refer to Wiring Diagrams.

TESTING

COLD CRANKING TEST




For complete starter wiring circuit diagrams, refer to Wiring Diagrams. The battery must be fully-charged and load-tested before proceeding. Refer to Battery in Battery.
1. Connect volt-ampere tester to battery terminals (1), (2) and (3). See instructions provided by manufacturer of volt-ampere tester being used.
2. Fully engage parking brake.
3. Place gearshift selector lever in Park position.
4. Verify that all lamps and accessories are turned off.
5. To prevent a gasoline engine from starting, remove Automatic Shutdown (ASD) relay. To prevent a diesel engine from starting, remove Fuel Pump Relay. These relays are located in Power Distribution Center (PDC). Refer to label on PDC cover for relay location.
6. Rotate and hold ignition switch in Start position. Note cranking voltage and current (amperage) draw readings shown on volt-ampere tester.
a. If voltage reads below 9.6 volts, refer to Starter Motor in Diagnosis and Testing. If starter motor is OK, refer to Engine Diagnosis in Engine for further testing of engine. If starter motor is not OK, replace faulty starter motor.
b. If voltage reads above 9.6 volts and current (amperage) draw reads below specifications, refer to Feed Circuit Test. Feed Circuit Test
c. If voltage reads 12.5 volts or greater and starter motor does not turn, refer to Control Circuit Testing. Control Circuit Testing
d. If voltage reads 12.5 volts or greater and starter motor turns very slowly, refer to Feed Circuit Test. Feed Circuit Test

NOTE: A cold engine will increase starter current (amperage) draw reading, and reduce battery voltage reading.