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Cold Cranking Test

Refer to STARTING/CHARGING  in SYSTEM WIRING DIAGRAMS for the location of complete starting system wiring diagrams. Before performing this test, be certain that the following procedures are accomplished:

  1. The battery is fully-charged and load tested. Refer to BATTERY SYSTEM for battery charging procedures and for battery diagnosis and testing procedures, including battery load test procedures.
  2. Fully engage the parking brake.
  3. If the vehicle is equipped with an automatic transmission, place the gearshift selector lever in the Park position. If the vehicle is equipped with a manual transmission, place the gearshift selector lever in the Neutral position and block the clutch pedal in the fully depressed position.
  4. Verify that all lamps and accessories are turned off.
  5. To prevent the engine from starting, remove the Automatic ShutDown (ASD) relay. The ASD relay is located in the Power Distribution Center (PDC), in the engine compartment. See the fuse and relay layout label affixed to the underside of the PDC cover for ASD relay identification and location.
  1. Connect a suitable volt-ampere tester to the battery terminals. See Fig 1. See the instructions provided by the manufacturer of the volt-ampere tester being used.
    Fig 1: Volts-Amps Tester Connections - Typical
    GC0026381Courtesy of DAIMLERCHRYSLER CORP.
    1 - POSITIVE CLAMP
    2 - NEGATIVE CLAMP
    3 - INDUCTION AMMETER CLAMP
  2. Rotate and hold the ignition switch in the Start position. Note the cranking voltage and current (amperage) draw readings shown on the volt-ampere tester.
    • If the voltage reads below 9.6 volts, refer to STARTER MOTOR  for starter motor diagnosis and testing procedures. If the starter motor tests OK, refer to appropriate ENGINE article for engine diagnosis engine diagnosis and testing procedures. If the starter motor is not OK, replace faulty starter motor.
    • If the voltage reads above 9.6 volts and the current (amperage) draw reads below specifications, refer to FEED CIRCUIT TEST  .
    • If the voltage reads 12.5 volts or greater and the starter motor does not turn, refer to CONTROL CIRCUIT TEST  .
    • If the voltage reads 12.5 volts or greater and the starter motor turns very slowly, refer to FEED CIRCUIT TEST  .
NOTE: A cold engine will increase the starter current (amperage) draw reading, and reduce the battery voltage reading.