Circuit Description
The electronic ignition system uses an individual ignition coil for each cylinder. The powertrain control module (PCM) controls the ignition operation through 6 ignition control (IC) circuits. Each ignition coil is connected to the PCM, power, or ground by the following circuits:
| • | The ground |
| • | The ignition 1 voltage |
| • | The appropriate IC control circuit |
The PCM triggers an ignition coil by grounding the appropriate IC control circuit using information from the crankshaft position (CKP) and camshaft position (CMP) sensors.
Diagnostic Aids
| • | The CKP signal is not needed to start and run. |
| • | Many situations may lead to an intermittent condition. Perform each inspection or test as directed. |
| Important: Remove any debris from the connector surfaces before servicing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion. |
| • | Inspect the PCM and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems. |
| • | For intermittent conditions, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Powertrain Control Module Connector End Views or Engine Controls Connector End Views | ||||||||||
1 | Did you perform the Diagnostic System Check - Vehicle? | -- | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information | ||||||
2 | Are DTCs P0335 or P0336 set? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | Go to Step 3 | ||||||
3 | Attempt to start the engine. Does the engine start and run? | -- | Go to Step 4 | Go to Step 15 | ||||||
4 | Observe the Misfire Current Counters parameter with a scan tool. Does the scan tool display any Misfire Current Counters incrementing? | -- | Go to Step 5 | Go to Diagnostic Aids | ||||||
Does spark jump the tester gap? | -- | Go to Step 11 | Go to Step 6 | |||||||
6 |
Is the voltage within 0.50 volts of the specified value? | B+ | Go to Step 7 | Go to Step 15 | ||||||
7 | Probe the ignition 1 voltage circuit of the affected ignition coil with a test lamp connected to the ignition coil ground circuit. Does the test lamp illuminate? | -- | Go to Step 8 | Go to Step 16 | ||||||
8 |
Does the frequency measure within the specified range? | 2-20 Hz | Go to Step 14 | Go to Step 9 | ||||||
9 |
Does the voltage measure greater than the specified value? | 1 V | Go to Step 17 | Go to Step 10 | ||||||
10 | Test the IC circuit for the following conditions:
Refer to Circuit Testing in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 21 | Go to Step 13 | ||||||
11 |
Does the scan tool display that the misfire followed that spark plug? | -- | Go to Step 20 | Go to Step 12 | ||||||
12 | Inspect the insulating spark plug boot and conducting spring for the following conditions:
Did you find and correct the condition? | -- | Go to Step 21 | Go to Symptoms - Engine Mechanical in Engine Mechanical | ||||||
13 | Test for an intermittent and for a poor connection at the powertrain control module (PCM). 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 21 | Go to Step 19 | ||||||
14 | Test for an intermittent and for a poor connection at the ignition coil. 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 21 | Go to Step 18 | ||||||
15 | Repair the open, high resistance, or short to ground in the ignition 1 voltage circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 21 | -- | ||||||
16 | Repair the open in the ignition coil ground circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 21 | -- | ||||||
17 | Repair the short to voltage in the IC circuit. Refer to Wiring Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 21 | -- | ||||||
18 | Replace the ignition coil. Refer to Ignition Coil Replacement . Did you complete the replacement? | -- | Go to Step 21 | -- | ||||||
19 | Replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | -- | Go to Step 21 | -- | ||||||
20 | Replace the spark plug. Refer to Spark Plug Replacement . Did you complete the replacement? | -- | Go to Step 21 | -- | ||||||
21 | Attempt to start the engine. Does the engine start and run? | -- | Go to Step 22 | Go to Step 2 | ||||||
22 |
Have any other DTCs not been diagnosed? | -- | Go to Diagnostic Trouble Code (DTC) List - Vehicle in Vehicle DTC Information | System OK | ||||||
