Cold Cranking Test

Fig 1: Connecting Volt-Ampere Tester To Battery Terminals - Typical

Courtesy of DAIMLERCHRYSLER CORP.

For complete starter wiring circuit diagrams, refer to the SYSTEM WIRING DIAGRAMS article. The battery must be fully-charged and load-tested before proceeding. Refer to the BATTERY SYSTEM article.

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 Shut Down (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.
   • If voltage reads below 9.6 volts, refer to DIAGNOSIS AND TESTING - STARTER MOTOR . If starter motor is OK, Refer to ENGINE DIAGNOSIS - MECHANICAL in appropriate ENGINE SERVICE INFORMATION article, for further testing of engine. If starter motor is not OK, replace faulty starter motor.
   • If voltage reads above 9.6 volts and current (amperage) draw reads below specifications, refer to FEED CIRCUIT TEST .
   • If voltage reads 12.5 volts or greater and starter motor does not turn, refer to CONTROL CIRCUIT TESTING .
   • If voltage reads 12.5 volts or greater and starter motor turns very slowly, refer to FEED CIRCUIT TEST .