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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2003 🢒 Grand Prix 🢒 Engine 🢒 Engine Electrical 🢒 Electronic Ignition (EI) System Diagnosis

Circuit Description

The ignition control module (ICM) has independent power and ground circuits. The circuits between the ICM and the powertrain control module (PCM) consist of the following circuits:

    • The IC timing signal
    • The IC timing control
    • The low-resolution engine speed signal
    • A low reference signal

The ICM sends 3X signals to the PCM. The ICM controls the timing advance during engine cranking. The timing advance changes to PCM control after the following actions:

    • The PCM receives the second 3X signal.
    • The PCM applies 5 volts to the IC timing signal circuit.

Diagnostic Aids
    • An arcing spark plug wire or an arcing ignition coil to the ICM may cause a stall, misfire or a no start condition.
    • The following may cause a no start condition:
       - Crankshaft reluctor wheel damage or improper installation
       - The CKP sensor coming in contact with the reluctor wheel
       - Foreign material passing between the CKP sensor and the reluctor wheel
    • Excess crankshaft end play will cause the CKP sensor reluctor wheel to move out of alignment with the CKP sensor. This could result in any of the following conditions:
       - A no start
       - A start and stall
       - Erratic performance
    • An improperly installed crankshaft could cause excess crankshaft end play.

Step

Action

Values

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Component Views or Powertrain Control Module Connector End Views

1

Did you perform the Diagnostic System Check-Engine Controls?

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Go to Step 2

Go to Diagnostic System Check - Engine Controls

2

Attempt to start the engine.

Does the engine start and run?

--

Go to Step 3

Go to Step 4

3
  1. Disconnect the CKP sensor B connector from the ignition control module (ICM).
  2. Measure the resistance from the CKP sensor 1 signal circuit to the low reference circuit of CKP sensor B with a DMM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Is the resistance within the specified range?

800-1,200 ohms

Go to Step 4

Go to Step 28

4
  1. Disconnect the crankshaft position sensor (CKP) A.
  2. Observe the 3X crank sensor parameter with a scan tool.
  3. Crank the engine.

Does the scan tool indicate a 3X crank sensor signal present?

--

Go to Step 5

Go to Step 11

5
  1. Connect the CKP sensor A.
  2. Test for spark at each cylinder with a J 26792 Spark Tester.

Did you observe any non-sparking cylinders?

9,868 per meter

Go to Step 6

Go to Step 9

6

Important: An arching spark plug wire or an arching ignition coil to the ICM may cause a stall or a no start condition.

  1. Inspect and test the affected cylinder spark plug wires, the ignition coils, and the spark plugs for a short to ground or an arching to ground. Refer to Circuit Testing in Wiring Systems, and Spark Plug Wire Inspection .
  2. If carbon tracking or corrosion is present, replace both components that are affected. Refer to Spark Plug Wire Replacement and Ignition Control Module Replacement .

Did you find and correct the condition?

--

Go to Step 32

Go to Step 7

7

Test the resistance of the spark plug wires.

Is the resistance more than the specified value?

3,000 ohms per foot

Go to Step 30

Go to Step 8

8

Measure the secondary resistance of the ignition coils.

Is the resistance within the specified range?

5,000-8,000 ohms

Go to Step 25

Go to Step 29

9
  1. Inspect the spark plug wires for proper routing and for the correct firing order.
  2. If any spark plug wires are found to be misrouted, reroute as necessary. Refer to Spark Plug Inspection .

Did you find and correct the condition?

--

Go to Step 32

Go to Step 10

10
  1. Remove the spark plugs. Refer to Spark Plug Replacement .
  2. Inspect spark plugs. Refer to Spark Plug Inspection .

Did you find the problem?

--

Go to Step 31

Go to Diagnostic Aids

11
  1. Connect the CKP sensor A.
  2. Disconnect the ICM.
  3. Turn ON the ignition.
  4. Connect a test lamp between the ICM ignition 1 voltage circuit and a good ground.

Does the test lamp illuminate?

--

Go to Step 12

Go to Step 24

12

Connect a test lamp between the ICM ignition 1 voltage circuit and the ICM ground circuit.

Does the test lamp illuminate?

--

Go to Step 13

Go to Step 26

13

Test for an intermittent and for a poor connection at the ICM. 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 32

Go to Step 14

14

  1. Disconnect the CKP sensor B connector from the ICM.
  2. Probe the CKP sensor 1 signal circuit of the CKP sensor B with a test lamp connected to battery voltage. Refer to Troubleshooting with a Test Lamp and Probing Electrical Connectors in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 17

Go to Step 15

15

Probe the CKP sensor 1 signal circuit of the CKP sensor B with a test lamp connected to a good ground. Refer to Troubleshooting with a Test Lamp and Probing Electrical Connectors in Wiring Systems.

Does the test lamp illuminate?

--

Go to Step 18

Go to Step 16

16

  1. Turn OFF the ignition.
  2. Measure the resistance from the CKP sensor 1 signal circuit and the low reference circuit of the CKP sensor B with the DMM at the ICM harness connector.

Is the resistance between the specified value?

800-1200 ohms

Go to Step 27

Go to Step 19

17

Test the CKP sensor 1 signal circuit for a short to ground. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 32

Go to Step 20

18

Test the CKP sensor 1 signal circuit for a short to voltage. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 32

Go to Step 17

19

Test the CKP sensor B circuits for the following conditions:

    • An open
    • The CKP sensor 1 signal and the low reference circuit shorted together

Did you find and correct the condition?

--

Go to Step 32

Go to Step 17

20

Test for an intermittent and for a poor connection at the ICM. 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 32

Go to Step 21

21

Test for an intermittent and for a poor connection at the CKP sensor. 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 32

Go to Step 22

22

  1. Remove the CKP sensor. Refer to Crankshaft Position Sensor Replacement .
  2. Visually inspect the CKP sensor for the following conditions:
    3. • Physical damage
    • Loose or improper installation
    • Wiring routed too closely to secondary ignition components
  3. Did you find and correct the condition?

--

Go to Step 32

Go to Step 23

23

Visually inspect the reluctor wheel for the following conditions:

    • Physical damage
    • Loose or improper installation

Refer to Crankshaft and Bearing Removal in Engine Mechanical.

Did you find and correct the condition?

--

Go to Step 32

Go to Step 28

24
  1. Repair the open or the short to ground in the ICM ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems.
  2. Replace the fuse if necessary.

Did you complete the repair?

--

Go to Step 32

--

25
  1. Remove the coils associated with the cylinder that did not have spark.
  2. Connect a test lamp across the ignition module primary circuit, between the ICM terminals for the coils. Refer to Troubleshooting with a Test Lamp in Wiring Systems.
  3. Observe the test lamp while cranking the engine.

Does the test lamp flash continuously while the engine is being cranked?

--

Go to Step 29

Go to Step 27

26

Repair the open in the ICM ground circuit. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 32

--

27

Replace the ICM. Refer to Ignition Control Module Replacement .

Did you complete the replacement?

--

Go to Step 32

--

28

Replace the CKP sensor B. Refer to Crankshaft Position Sensor Replacement .

Did you complete the replacement?

--

Go to Step 32

--

29

Replace the affected ignition coils. Refer to Ignition Coil Replacement .

Did you complete the replacement?

--

Go to Step 32

--

30

Replace the spark plug wires. Refer to Spark Plug Wire Replacement .

Did you complete the replacement?

--

Go to Step 32

--

31

Replace the spark plugs. Refer to Spark Plug Replacement .

Did you complete the replacement?

--

Go to Step 32

--

32
  1. Turn the ignition OFF for 30 seconds.
  2. Start the engine and operate the vehicle.
  3. Observe the malfunction indicator lamp (MIL), vehicle performance and drivability.

Does the vehicle operate normally, with no MIL?

--

System OK

Go to Step 2