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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Corvette 🢒 Engine 🢒 Engine Electrical 🢒 Battery Is Undercharged or Overcharged

Battery Is Undercharged or Overcharged Low/High Voltage Message

Battery is Undercharged or Overcharged (DIC-Low or High Voltage warning message)

Step

Action

Value(s)

Yes

No

DEFINITION: The LOW VOLTAGE or HIGH VOLTAGE message is displayed across the driver information center.

1

Were you sent here from the Charging System Check?

--

Go to Step 2

Go to Charging System Check

2
  1. Recharge the battery if necessary. Refer to Battery Charging .
  2. Load test the battery.

Does the battery pass the load test?

--

Go to Step 4

Go to Step 3

3

Replace the battery. Refer to Battery Replacement .

Is the repair complete?

--

Go to Charging System Check

--

4
  1. Start the engine and allow it to idle in park.
  2. Load the electrical system by turning on the highbeam headlamps and the heater blower to high.
  3. Connect a DMM to the vehicle battery and measure the voltage.

Is the voltage within specified values?

13.5-15.0 V

Go to Charging System Check

Go to Step 5

5
  1. Connect the red alligator clip of the J 41450-B CS Generator Electronic Tester to the generator output terminal.
  2. Connect the black alligator clip to the generator housing.
  3. The green POWER lamp of the tester should light and remain lighted while the tester is being used.

Does the green POWER lamp of the tester light?

--

Go to Step 6

Go to Step 7

6
  1. With the alligator clips connected.
  2. Disconnect the generator four way connector.
  3. Locate the matching four way connector of the J 41450-B and connect it to the generator.

Does the red DIAGNOSTIC lamp of the tester light?

--

Go to Step 8

Go to Step 30

7

Repair the open in the generator output circuit or the battery ground circuit.

Is the repair complete?

--

Go to Charging System Check

--

8
  1. Prior to connecting a carbon pile load tester, make sure that the load dial is completely turned to the off position.
  2. Connect the leads of the carbon pile to the vehicle battery.
  3. Connect an inductive ammeter to the generator output circuit.
  4. Start the engine and allow it to idle.

Does the red DIAGNOSTIC lamp of the tester light?

--

Go to Step 30

Go to Step 9

9

Increase the engine speed to 2500 RPM.

Does the red DIAGNOSTIC lamp of the tester light?

--

Go to Step 30

Go to Step 10

10
  1. Maintain the engine speed at 2500 RPM
  2. Turn on the load of the carbon pile tester.
  3. Using caution not to load the battery beyond manufacturers load test values, increase the load while monitoring generator output current.

As the load is increased, is the generator capable of producing the amount of load test current specified in generator usage?

Refer to Generator Usage .

--

Go to Step 11

Go to Step 12

11

With the engine speed at 2500 RPM and the generator operating at load test value, is the red DIAGNOSTIC lamp of the tester lighted?

--

Go to Step 30

Go to Step 12

12
  1. Maintain the engine speed at 2500 RPM and continue to operate the generator at the load test value.
  2. Using a DMM measure the voltage from the generator output terminal to the battery positive terminal.

Is the voltage under the specified value?

0.5 V

Go to Step 13

Go to Step 14

13
  1. Maintain the engine speed at 2500 RPM and continue to operate the generator at the load test value.
  2. Using a DMM measure the voltage from the generator housing to the battery negative terminal.

Is the voltage under the specified value?

0.5 V

Go to Step 16

Go to Step 15

14
  1. Turn off the engine.
  2. Disconnect the battery negative terminal.
  3. Inspect the circuit between the battery positive terminal and the generator output terminal for high resistance.
  4. Disassemble and clean or replace the terminals and wire in this circuit as necessary.

Is the repair complete?

--

Go to Charging System Check

--

15
  1. Turn off the engine.
  2. Inspect the circuit between the negative battery terminal and the generator housing for high resistance.
  3. Disassemble and clean or replace the terminals and wire in this circuit as necessary.

Is the repair complete?

--

Go to Charging System Check

--

16
  1. Turn the ignition switch to the off position.
  2. Disconnect the negative battery terminal.
  3. Disconnect the circuit 2 from the starter terminal.
  4. Using a DMM measure the resistance of this circuit from the generator four wire connector terminal D to the starter connector terminal.

Is the resistance within specified values?

0-2 ohms

Go to Step 18

Go to Step 17

17

Repair the open in circuit 2 between the starter terminal and the generator connector.

Is the repair complete?

--

Go to Charging System Check

--

18
  1. Disconnect the powertrain control module connector C2.
  2. Connect a DMM between the powertrain control module connector C2 terminal 52 and the generator four wire connector terminal C.
  3. Measure the resistance of circuit 23.

Is the resistance within specified values?

0-2 ohms

Go to Step 19

Go to Step 24

19

With the powertrain control module connector C2 and the generator four wire connector disconnected, measure the resistance to ground of circuit 23.

Is circuit 23 shorted to ground?

--

Go to Step 20

Go to Step 25

20

With the powertrain control module connector C2 and the generator four wire connector disconnected, measure circuit 23 for a short to voltage.

Is circuit 23 shorted to voltage?

--

Go to Step 26

Go to Step 21

21
  1. Disconnect the powertrain control module connector C2.
  2. Connect a DMM between the powertrain control module connector C2 terminal 15 and the generator four wire connector terminal B.
  3. Measure the resistance of circuit 225.

Is the resistance within specified values?

--

Go to Step 22

Go to Step 27

22

With the powertrain control module connector C2 and the generator four wire connector disconnected, measure the resistance to ground of circuit 225.

Is circuit 225 shorted to ground?

--

Go to Step 23

Go to Step 28

23

With the powertrain control module connector C2 and the generator four wire connector disconnected, measure circuit 225 for a short to voltage.

Is circuit 225 shorted to voltage?

--

Go to Step 29

Go to Charging System Check

24

Repair the open in circuit 23.

Is the repair complete?

--

Go to Charging System Check

--

25

Repair the short to ground in circuit 23.

Is the repair complete?

--

Go to Charging System Check

--

26

Repair the short to voltage in circuit 23.

Is the repair complete?

--

Go to Charging System Check

--

27

Repair the open in circuit 225.

Is the repair complete?

--

Go to Charging System Check

--

28

Repair the short to ground in circuit 225.

Is the repair complete?

--

Go to Charging System Check

--

29

Repair the short to voltage in circuit 225.

Is the repair complete?

--

Go to Charging System Check

--

30
  1. Disconnect the powertrain control module connector C2, and the generator four wire connector.
  2. Turn the ignition switch to the on position.
  3. Measure circuit 225 for a short to voltage.

Is circuit 225 shorted to voltage?

--

Go to Step 31

Go to Step 32

31

Repair the short to voltage in circuit 225.

Is the repair complete?

--

Go to Step 32

--

32

Replace or repair the generator. Refer to Generator Replacement .

Is the repair complete?

--

Go to Charging System Check

--