Operation CHARM: Car repair manuals for everyone.

Cold Cranking Test

COLD CRANKING TEST
For complete starter wiring circuit diagrams, refer to Wiring Diagrams. The battery must be fully-charged and load-tested before proceeding.

Fig. 1 Volts-Amps Tester Connections - Typical:




1. Connect volt-ampere tester to battery terminals (Fig. 1). See instructions provided by manufacturer of volt-ampere tester being used.

NOTE: Certain diesel equipped models use dual batteries. If equipped with dual battery system, tester should be connected to battery on left side of vehicle only Also, tester current reading must be taken from positive battery cable lead that connects to starter motor.

2. Fully engage parking brake.
3. If equipped with manual transmission, place gearshift selector lever in Neutral position and block clutch pedal in fully depressed position. If equipped with automatic transmission, 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.

WARNING: IF EQUIPPED WITH DIESEL ENGINE, ATTEMPT TO START ENGINE A FEW TIMES BEFORE PROCEEDING WITH FOLLOWING STEP.

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 Diagnosis and Testing. If starter motor is OK, refer to Engine Diagnosis for further testing of the 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.
c. If voltage reads 12.5 volts or greater and starter motor does not turn, refer to Control Circuit Testing.
d. If voltage reads 12.5 volts or greater and starter motor turns very slowly, refer to Feed Circuit Test.

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