Cold Cranking Test
NOTE:
See SYSTEM WIRING DIAGRAMS
for complete starter wiring circuit diagrams.
- Fully charge and load-test the battery. Refer to Electrical/Battery System - Diagnosis and Testing .
- Connect volt-ampere tester leads (1 and 2 to the battery terminals. Connect volt-ampere tester lead (3) around the positive battery cable. 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.
- Place transmission in Park or Neutral with the parking brake set (depending on transmission application).
- If equipped with manual transmission, block clutch pedal in fully depressed position.
- Verify that all lamps and accessories are turned off.
- To prevent a gasoline engine from starting, remove Automatic ShutDown (ASD) relay. To prevent a diesel engine from starting, remove Fuel Pump Relay. See SYSTEM WIRING DIAGRAMS
for relay locations.WARNING: Attempt to start engine a few times before proceeding with following step.NOTE: A cold engine will increase starter current (amperage) draw reading, and reduce battery voltage reading.
- Rotate and hold ignition switch in Start position. Note cranking voltage and current (amperage) draw readings shown on volt-ampere tester.
- If voltage reads below 9.6 volts, see starter motor diagnosis and testing. See Diagnosis and Testing . If starter motor is OK, See - Engine Diagnosis in appropriate Engine service information article. for further diagnosis and testing of the engine. If starter motor is not OK, replace the starter motor. See Removal .
- See Feed Circuit Test if voltage reads above 9.6 volts and current (amperage) draw reads below specifications.
- See Feed Circuit Test if voltage reads 12.5 volts or greater and starter motor does not turn or turns very slowly.