GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Starting and Charging Schematics

Connector End View Reference: Master Electrical Component List

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Turn the ignition to the START position.

Does the engine crank?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

3

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

Does the scan tool display Park or Neutral?

Go to Step 4

Go to Range Selector Displays Incorrect Range

4

  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Starter Relay Command parameter in the PCM/ECM data list.
  3. Turn the ignition to the START position.

Does the scan tool display Yes?

Go to Step 6

Go to Step 5

5

  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool, observe the Starter Switch parameter in the BCM data list.
  3. Turn the ignition to the START position.

Does the scan tool display Yes?

Go to Step 15

Go to Power Mode Mismatch

6

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

Does the test lamp illuminate?

Go to Step 7

Go to Step 16

7

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

Does the test lamp illuminate?

Go to Step 8

Go to Step 12

8

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

Does the test lamp illuminate?

Go to Step 9

Go to Step 17

9

Important:  The engine may crank during the following step.

  1. Turn OFF the ignition.
  2. Connect a 30-amp fused jumper between the battery positive voltage circuit of the crank relay switch and the starter solenoid crank voltage circuit of the crank relay.

Does the engine crank?

Go to Step 13

Go to Step 10

10

Does the fuse in the jumper open?

Go to Step 18

Go to Step 11

11

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

Did you find and correct the condition?

Go to Step 22

Go to Step 14

12

Test the control circuit of the crank relay for an open or short to battery voltage. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 22

Go to Step 15

13

Inspect for poor connections at the crank relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 22

Go to Step 19

14

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

Did you find and correct the condition?

Go to Step 22

Go to Step 20

15

Inspect for poor connections at the harness connector of the PCM/ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 22

Go to Step 21

16

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

Did you complete the repair?

Go to Step 22

--

17

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

Did you complete the repair?

Go to Step 22

--

18

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

Did you complete the repair?

Go to Step 22

--

19

Replace the crank relay.

Did you complete the replacement?

Go to Step 22

--

20

Replace the starter motor. Refer to Starter Motor Replacement .

Did you complete the replacement?

Go to Step 22

--

21

Replace the PCM/ECM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 22

--

22

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2