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For 1990-2009 cars only

Delphi CS-144 (KG9) and Valeo A13VI+ (K68)

When the charging system is operating normally, the charge indicator lamp will come on when the ignition switch is turned ON and will go out when the engine starts. If the lamp operates abnormally, refer to Charge Indicator Always On or Charge Indicator Inoperative . If an undercharged or overcharged battery condition occurs, refer to Battery Is Undercharged or Overcharged . Automotive generators produce a certain amount of low level sound during normal operation. This sound is caused by a combination of mechanical and electrical/magnetic conditions in the generator. Typically, the sound level will be higher during periods of high output demand on the generator. Objectionable noise from a generator may be caused by conditions causing normal sound to be transmitted directly to the passenger compartment, by mounting problems, or by internal generator conditions. The following can cause objectionable noise:

    • Improper routing of hoses, wiring, shielding, etc., against the generator housing.
    • Loose drive pulley
    •  Loose mounting bolts
    • Mounting the generator in a bind.
    • Worn or dirty bearings
    • A faulty or damaged diode, stator, or rotor

Delphi CS-144 (KG9)

Tools Required

J 41450-B J 41450-B

To diagnose a CS generator use the following procedure:

  1. Turn the ignition switch OFF. Turn all electrical accessory loads OFF.
  2. Turn the load in the carbon pile load tester all the way OFF. Connect load test across the battery terminals. Refer to Starting and Charging Schematics to be sure the ammeter clip is placed for the entire generator output to pass through the clip. If circuits are split so that any of the current can pass through parallel circuits, all such circuits must pass through the clip or the generator output reading on the inductive ammeter will not be accurate.
  3. Install the inductive ammeter around the output wire(s) of the generator.
  4. Perform the universal tester self-test procedure per the manufacturer's instructions to verify proper operation of the tester.
  5. Connect the red alligator clip of the tester to the generator output terminal. Connect the black clip to the metal generator housing. The green POWER lamp on the tester should light. If the green POWER lamp does light, go to step 8. If the green POWER lamp does not light, go to step 6.
  6. Use a digital multimeter to check the voltage between the generator output terminal and the battery negative terminal. If the reading is B+ voltage, go to step 7. If not, check for an open condition in the generator output wiring and repair as necessary. If the tester's green POWER lamp now lights when connected per step 5, go to step 8. If no open condition was found or the green POWER lamp still does not light, go to step 7.
  7. With the tester still connected as described in step 5, connect a jumper wire between the generator metal housing and the battery negative terminal. The green POWER lamp on the tester should light. If the green POWER lamp does light, check the ground path from the generator housing to the battery negative terminal for open conditions and repair as necessary. If the tester's green POWER lamp now lights, go to step 8. If not, return to step 1 and repeat the procedure, including the tester self-test.
  8. With the tester still connected as described in step 5, disconnect the 4-way generator connector from the generator and connect the matching connector on the tester to the generator. The red DIAGNOSTIC lamp on the tester should light. If the red DIAGNOSTIC lamp lights, go to step 10. If the red DIAGNOSTIC lamp does not light, go to step 9.
  9. Disconnect the 4-way tester connector from the generator. With the ignition key in RUN (engine stopped), use a fused jumper lead (with a 5 A fuse) and Metri-Pack 150 terminal probe adapter to ground the L terminal (cavity B) in the vehicle harness 4-way connector. If the fuse does not blow, replace the generator. If the fuse blows, refer to Starting and Charging Schematics to diagnose and repair the L terminal circuit (225) for direct short to B+ or mis-wired/no resistance condition, then replace the generator. Fix the wiring before replacing the generator.
  10. Turn OFF all the electrical accessories and close the doors to be sure all the loads are off. With the tester connected as described in step 8, start the engine and let the engine idle briefly. (Note that the vehicle's generator control circuits are bypassed during this test, and the charge indicator in the instrument cluster will not operate normally.) After the engine starts, the red DIAGNOSTIC lamp on the tester should not be lit. If the red DIAGNOSTIC lamp is still lit, replace the generator. If the red DIAGNOSTIC lamp is not lit, go to step 11.
  11. Increase the engine speed to 2500 RPM. The red DIAGNOSTIC lamp on the tester should not light. If the red DIAGNOSTIC lamp lights, replace the generator. If the red DIAGNOSTIC lamp is not lit, go to step 12.
  12. With the engine speed still at 2500 RPM, turn the load on the carbon pile load tester to ON and adjust until the generator output is at the load test value. Refer to Generator Usage . If the red DIAGNOSTIC lamp on the tester lights with the generator operating at or below the load test output value, replace the generator. If the red light does not light and the load test value is attained, the generator is good. DO NOT replace the generator. Go to step 13.
  13. Turn the carbon pile load tester load to OFF and stop the engine. Remove the generator tester, ammeter, and load tester from the vehicle. Reconnect the 4-way harness connector to the generator. Be sure the connector is fully seated and latched.
  14. • If the customer has commented about erratic or high voltage from a generator that uses an S terminal connection, be sure to check the S terminal circuit (cavity D in the harness connector) for intermittent or high resistance connections.
    •  If the customer has commented about a battery that loses charge over a period of time, refer to Battery Electrical Drain/Parasitic Load Test .

Valeo A13VI+ (K68)

Tools Required

J 39200 Digital Multimeter or equivalent

To diagnose the Valeo A13VI+ (K68) generator, use the following procedure:

  1. Turn the ignition switch ON without starting the engine.
  2. Using a DMM, measure and record the battery voltage. The charge indicator should be on. If the indicator is not lit, disconnect the generator electrical connector and ground the L terminal in the electrical connector.
  3. • If the indicator lights, repair or replace the generator.
    •  If the indicator does not light, locate and repair open circuit between grounding lead and ignition switch. The charge indicator bulb may be burned out.
  4. With ignition switch ON and the engine running, the charge indicator lamp should not be lit. If the lamp is lit, turn the engine OFF and disconnect the 4-way harness connector from the generator. Turn the ignition ON and start the engine.
  5. • If the charge indicator lamp does not light, repair or replace the generator.
    • If the charge indicator lamp is still lit, check for a grounded L terminal wire in the harness.
  6. With the ignition switch ON and the engine not running, connect the DMM from the ground to the generator connector L terminal. This terminal should have battery voltage. If low or zero volts is indicated, high resistance or an open exists in the circuit. Refer to Starting and Charging Schematics .
  7. Connect the DMM from the battery negative terminal to the generator output BAT terminal. This reading should also be battery voltage. If low or zero volts is indicated, high resistance or an open exists in the circuit. Refer to Starting and Charging Schematics .
  8. Reconnect the wiring harness connector to the generator. Start and run the engine at a moderate speed (above 1000 RPM), with the electrical loads and accessories OFF.
  9. Use the DMM to measure the voltage across the battery.
  10. • If the voltage is above 16 volts, replace the generator.
    • If the voltage is below the battery voltage measured in step 2, inspect the circuit between the generator output terminal and the battery for chafing, corrosion, or breaks. If no problems are found, replace the generator.
  11. Disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  12. Disconnect the wiring harness from the generator output BAT terminal.
  13. Important: Insulate the ammeter to generator and wiring harness connections to make sure that there is no contact to any exposed metal surfaces that could potentially cause a short.

  14. Install an ammeter between the generator output BAT terminal and the engine wiring harness.
  15. Reconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection .
  16. With the load test OFF, connect a carbon pile load tester across the battery terminals.
  17. Start the engine. Run the engine at a moderate speed (2500 RPM).
  18. Turn the carbon pile load ON and adjust to the proper load test value. Refer to Generator Usage . Use the DMM to check the voltage across the battery terminals:
  19. • If the voltage is above 13 volts, the generator is GOOD.
    • If the voltage falls below 13 volts, repair or replace the generator.
    • If the load test value cannot be attained and the voltage falls below 13 volts, repair or replace the generator. (If load test value can not be attained but voltage does not fall below 13 volts, a carbon pile tester problem is indicated. Check for low ampere capacity of test load.)