LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2003 >> Liberty Limited, 4WD, Part Time, 42RLE >> Repair and Diagnosis >> Electrical >> Charging Systems >> Charging System - Generators & Regulators >> System Tests >> Checking Charging System Performance With No DTC'S >> Testing

Checking Charging System Performance With No DTC'S: Testing

    NOTE: Verify that the battery is able to pass a load test before continuing.
  1. Turn the ignition on, engine not running. With the DRBIII®, read battery voltage and record the results. Measure battery voltage between the battery positive and negative terminals and record the results. Compare the 2 voltage readings. If the voltage difference is less than one volt, go to next step. If the difference is greater than one volt, go to step  8.
    2. CAUTION: Ensure all wires are clear of the engine's moving parts.
  2. Turn the ignition on, engine not running. Measure the voltage between the generator B+ terminal and the battery positive circuit between the generator and the battery. Start the engine. If the voltage is above 0.4 volt, repair the excessive resistance in the battery positive circuit between the generator and battery. Perform POWERTRAIN VERIFICATION TEST VER-3 . If the voltage is not above 0.4 volt, go to next step.
  3. Turn ignition on, engine not running. Record all DTC's and Freeze Frame data. Erase codes. Carefully inspect all connectors for corrosion or spread terminals before continuing. With the DRBIII®, actuate the generator field driver. Measure the voltage of the (K125) generator field source circuitry by backprobing the back of the generator field harness connector. If the voltage is above 10.0 volts, go to next step. If the voltage is not above 10.0 volts, repair the (K125) generator field source circuit for an open or short to ground. Perform POWERTRAIN VERIFICATION TEST VER-3 .
    4. CAUTION: Ensure all wires are clear of the engine's moving parts.
  4. Start the engine. Warm the engine to operating temperature. Measure the voltage between the generator case and battery negative post. If the voltage is above 0.1 volt, repair the excessive resistance in the generator ground circuit between the generator case and battery ground side. Perform POWERTRAIN VERIFICATION TEST VER-3 . If the voltage is not above 0.1 volt, go to next step.
  5. Turn the ignition off. Disconnect the generator field harness connector at back of the generator. Measure resistance across the generator field terminals at the generator. If the resistance is above 15 ohms, replace or repair the generator as necessary. If the resistance is not above 15 ohms, go to next step.
  6. Disconnect the PCM harness connectors. Measure the resistance of the (K20) generator field driver circuit between the PCM harness connector and the generator harness connector. If the resistance is below 5 ohms, go to next step. If the resistance is not below 5 ohms, repair the open in the (K20) generator field driver circuit. Perform POWERTRAIN VERIFICATION TEST VER-3 .
    7. NOTE: Before continuing, check the PMC harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
  7. Using a wiring diagram as a guide, inspect the wire harness and connectors. Pay particular attention to all power and ground circuits. If there are no possible causes remaining, replace and program the PCM. See PROGRAMMING POWERTRAIN CONTROL MODULE . Perform POWERTRAIN VERIFICATION TEST VER-3 .
    8. NOTE: Battery condition must be verified prior to this test.
  8. Turn the engine off. Inspect the generator belt tension and condition. If the generator belt is okay, go to next step. If the belt is not okay, repair as necessary. Perform POWERTRAIN VERIFICATION TEST VER-3 .
  9. Start the engine. Turn on all accessories. Raise engine speed to 2000 rpm for 30 seconds then return to idle. With the DRBIII®, read DTC's. If there are any "CHARGING SYSTEM" trouble codes, refer to symptom list for related charging DTC's. Perform POWERTRAIN VERIFICATION TEST VER-3 . If there are no DTC's, go to next step.
  10. Turn ignition on, engine not running. With the DRBIII®, actuate the generator field driver. Using a 12-volt test light, backprobe the generator field driver terminal at the back of the generator. The test light should blink ON and OFF everY 1.4 seconds. While monitoring the 12-volt test light, wiggle the field terminals back to the PCM and ADS relay. If there was any interruption in the normal cycle of the test light, repair the wire or connector where the wiggling interrupted the voltage cycle. If the there was no interruption, test is complete.
scientia non olet · About LEMON Manuals