GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Starting and Charging Schematics

1

Did you perform the Engine Electrical Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Engine Electrical

2

Turn the ignition to the START position.

Does the engine crank?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Install a scan tool.
  2. Verify that the transmission is in Park or Neutral.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the IMS parameter in the PCM data list.

Does the scan tool display Park or Neutral?

Go to Step 4

Go to Range Selector Displays Incorrect Range in Automatic Transaxle - 4T80 - E

4

  1. With a scan tool, observe the Crank Request Signal parameter in the PCM data list.
  2. Turn the ignition to the START position.

Does the scan tool display Yes?

Go to Step 5

Go to Step 10

5

  1. Turn OFF the ignition.
  2. Disconnect the Starter relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage of the Starter relay coil circuit and a good ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 18

6

  1. Connect a test lamp between the battery positive voltage of the Starter relay coil circuit and the control circuit of the Starter relay.
  2. Turn the ignition to the START position.

Does the test lamp illuminate?

Go to Step 7

Go to Step 11

7

  1. Turn OFF the ignition.
  2. Connect a test lamp between the battery positive voltage of the Starter relay switch circuit and a good ground.

Does the test lamp illuminate?

Go to Step 8

Go to Step 19

8

Connect a 50 amp fused jumper between the battery positive voltage of the Starter relay switch circuit and the starter solenoid crank voltage circuit.

Does the engine crank?

Go to Step 14

Go to Step 9

9

Does the fuse in the jumper open?

Go to Step 20

Go to Step 13

10

  1. Turn OFF the ignition.
  2. Disconnect the PCM.
  3. Connect a test lamp between the crank voltage circuit of the PCM and a good ground.
  4. Turn the ignition to the START position.

Does the test lamp illuminate?

Go to Step 17

Go to Step 12

11

Test the control circuit of the Starter relay for a high resistance or short to battery voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 17

12

Test the crank voltage circuit of the PCM for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 16

13

Test the starter solenoid crank voltage circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 15

14

Inspect for poor connections at the Starter relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 21

15

Inspect for poor connections at the starter solenoid. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 22

16

Inspect for poor connections at the ignition switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 23

17

Inspect for poor connection at the PCM harness connector C1. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 24

18

Repair the open or high resistance in the battery positive voltage of the Starter relay coil circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

--

19

Repair the open or high resistance in the battery positive voltage of the Starter relay switch circuit. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

--

20

Repair the short to ground in the crank voltage circuit of the starter solenoid. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

--

21

Replace the Starter relay.

Did you complete the replacement?

Go to Step 25

--

22

Replace the Starter Motor. Refer to Starter Motor Replacement .

Did you complete the replacement?

Go to Step 25

--

23

Replace the Ignition Switch. Refer to Ignition Switch Replacement - On Vehicle in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 25

--

24

Important: Perform the set up procedures for the PCM. Refer to Powertrain Control Module Programming in Engine Controls - 4.6L.

Replace the PCM. Refer to Powertrain Control Module Replacement in Engine Controls - 4.6L.

Did you complete the replacement?

Go to Step 25

--

25

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2