GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important: The J 35616-A Connector Test Adapter Kit must be used whenever a diagnostic procedure requires checking or probing a terminal. Using the adapter will ensure that no damage to the terminal will occur, as well as giving an idea of whether contact tension is sufficient. If contact tension seems incorrect, refer to Checking Terminal Contact in General Electrical Diagnosis Procedures for specifics.

1

  1. Disconnect the generator connector.
  2. Turn the ignition switch to the RUN position.
  3. Attach a scan tool to the DLC.
  4. Clear any DTC.
  5. Select Misc Tests, Eng Outputs, and Gen L Term.
  6. Command the generator ON.
  7. Use a DMM in order to measure the voltage from the generator connector terminal L to ground.

Is the voltage near the specified value?

5 V

Go to Step 2

Go to Step 6

2

Use a DMM in order to measure the voltage from the generator battery terminal to ground.

Is the voltage equal to the specified value?

B+

Go to Step 3

Go to Step 9

3

  1. Reconnect the generator connector.
  2. Ensure that all of the accessories are OFF.
  3. Engine running at fast idle.
  4. Use a DMM in order to measure the voltage across the battery.

Is the voltage within the specified range?

13-16 V

Go to Step 4

Go to Step 10

4

Inspect the generator. Refer to Charging System Check .

Does the generator test OK?

--

Go to Step 5

Go to Step 10

5

Replace the battery. Refer to Battery Replacement .

Is the repair complete?

--

System OK

--

6

Use a DMM in order to test for a poor connection or an open in circuit 225.

Is there a poor connection or an open in circuit 225?

--

Go to Step 7

Go to Step 8

7

Repair the poor connection or open in circuit 225.

Is the repair complete?

--

System OK

--

8

Service the PCM. Refer to Powertrain Control Module Replacement/Programming in Engine Controls - 3.1L or Powertrain Control Module Replacement/Programming in Engine Controls - 3.8L.

Is the repair complete?

--

System OK

--

9

Repair the open in circuit 2 or fusible link to the generator battery terminal.

Is the repair complete?

--

System OK

--

10

Replace the generator. Refer to Generator Replacement or Generator Replacement .

Is the repair complete?

--

System OK

--