Fuel System > Engine Control System

Component Location

General Description

With the ignition switch in the ON or START position, voltage is applied to the ignition coil. Each ignition coil consists of two coils. High tension leads go to each cylinder from the ignition coils. The ignition coils fire two spark plugs on every power stroke (the cylinder under compression and the cylinder on the exhaust stroke). The Engine Control Module (PCM) provides a switching circuit to ground for primary coil circuit control. The PCM uses the crankshaft position sensor and camshaft position sensor signal to time the energizing of the coil. When a primary ignition coil is energized and de-energized, the secondary coil produces a high voltage spike to the attached spark plugs.

DTC Description

Checking output signals from ignition coils every 10 sec. under detecting condition, if the signals indicating open or short in the circuit are detected for more than 5 sec., PCM sets this DTC. MIL(Malfunction Indication Lamp) turns on when the malfunction lasts till consecutive 2 driving cycle.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

•	Detects a short to ground, to battery or open circuit

•	Poor connection

•	Open or short in harness

•	Ignition Coil

•

PCM

EnableConditions

•	NO DTC related to this item

•	Engine running

•	11V ≤ Battery voltage ≤ 16V

•	The above conditions are met > 0.5 sec.

Threshold value

•	Open or short

DiagnosisTime

•	Continuous (More than 5 sec.failure for every 10 sec.test)

MIL On Condition

•	2 driving cycles

Specification

Resistance (Ω)	Primary Coil	Secondary Coil
Resistance (Ω)	0.62 ± 10% (Ω)	7.0 ± 15% (kΩ)

Schematic Diagram

Monitor DTC Status

Check DTC Status

(1)	Connect scantool to Data Link Connector(DLC).

(2)

IG "ON".

(3)	Select "DTC" button, and then Press "DTC Status" to check DTC's information from the DTCs menu.

(4)	Read "DTC Status" parameter.

(5)

Is parameter displayed "Present fault"?

	▶ Go to "Terminal and connector inspection" procedure.
	▶ Fault is intermittent caused by poor contact in the sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, ending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

Terminal And Connector Inspection

1.	Many malfunctions in the electrical system are caused by poor harness and terminal condition. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

2.	Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

	▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure
	▶ Go to " Power Circuit Inspection " procedure.

Power Circuit Insepction

■ Check voltage

1.	IG "OFF" and disconnect Ignition Coil #2 connector.

2.	IG "ON" and ENG "OFF"

Measure voltage between power terminal of ignition coil #2 harness connector and chassis ground.

Specification : Approx. B+

Is the measured voltage within specification ?

	▶ Go to "Control Circuit Inspection" procedure.
	▶ Check fuse connected to ignition coil for open. ▶ Repair open in harness, and go to "Verification of Vehicle Repair" procedure.

Control Circuit Inspection

■ Check short to battery in harness

1.	IG "OFF" and disconnect ignition coil #2connector and PCM connector.

Measure resistance between power and control terminals of ignition coil #2 harness connector.

Specification : Infinite

Is the measured resistance within specification?

	▶ Go to "Check short to ground in harness" as follows.
	▶ Repair short to battery in harness, and go to "Verification of Vehicle Repair" procedure.

■ Check short to ground in harness

1.	IG "OFF" and disconnect ignition coil #2 connector and PCM connector.

Measure resistance between control terminal of ignition coil #2 harness connector and chassis ground.

Specification : Infinite

Is the measured resistance within specification?

	▶ Go to "Check open in harness" as follows.
	▶ Repair short to ground in harness, and go to "Verification of Vehicle Repair" procedure.

■ Check open in harness

1.	IG "OFF" and disconnect Ignition Coil #2 connector and PCM connector.

Measure resistance between control terminal of Ignition Coil #2 harness connector and IG Coil #2 control terminal of PCM harness connector.

Specification : Below 1Ω

Is the measured resistance within specification?

	▶ Go to "Component Inspection" procedure.
	▶ Repair open in harness, and go to "Verification of Vehicle Repair" procedure.

Component Inspection

■ Check Ignition Coil

1.	IG "OFF" and disconnect ignition coil connector.

2.	Measure resistance between power and signal terminals of ignition coil connector.(Measurement "A")

Measure resistance between power terminal of ignition coil connector and out terminal of secondary ignition coil.(Measurement "B")

Specification :

Resistance (Ω)	Primary Coil (A)	Secondary Coil (B)
Resistance (Ω)	0.62 ± 10% (Ω)	7.0 ± 15% (kΩ)

Is the measured resistance within specification?

	▶ Substitute with a known - good PCM and check for proper operation. If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
	▶ Substitute with a known - good Ignition Coil and check for proper operation. If the problem is corrected, replace Ignition Coil and go to "Verification of Vehicle Repair" procedure.

There is a memory reset function on scantool that can erase optional parts automatically detected and memorized by PCM. After testing PCM on the vehicle, use this function to reuse the PCM on the others

Verification Of Vehicle Repair

After a repair, it is essential to verify that the fault has been corrected.

1.	Connect scantool and select "DTC" button.

2.	Press "DTC Status" button and confirm that "DTC Readiness Flag" indicates "Completed". If not, drive the vehicle within conditions noted in the freeze frame data or enable conditions

3.	Read "DTC Status" parameter

Is parameter displayed "History(Not Present) fault"?

	▶ System performing to specification at this time. Clear the DTC
	▶ Go to the applicable troubleshooting procedure.