4.
Check ignition timing.
caution
The data shown above is only for reference and there may be a little difference actually.
This is the inspection procedure to determine whether it is present DTC or memoried one by monitoring the current signal or by using the function of oscilloscope with Hi-scan pro.
Connect scan tool to DLC.
IG KEY : ON
Start engine and warm up to operating temperature.
Check ignition timing.
The data shown above is only for reference and there may be a little difference actually.
Specification
Idle : 0 ~ 20˚ BTDC
3000 rpm : 29 ~ 49˚ BTDC
Start engine and warm up to operating temperature.
Probe(+) : Ignition coil #1,#2 harness connector NO2.
Probe(-) : Chassis ground.
This figures show the waveform of primary coil measured at terminal 2 of ignition coil at idle.
The voltage at point ① is power supply of IG coil and it should be battery voltage
The signal at ② is the duration when power TR in ECM is ON named DWELL and its normal voltage is below 0.5V.
In case over 0.5V
Possible cause: Faulty power TR in ECM or poor ECM ground connection.
The waveform at ③ is surge voltage which occures at primary coil when power TR off and its normal voltage is over 320V.
In case when surge voltage is low
Possible cause: Open circuit in power line or poor ground connection.
In case there is no symptom and wrong data but DTC is shown
The problem may be intermittent so slightly shake the connector and harness vertically and horizontally to check if there is any data changes
If the data changes normally, the problem was intermittent so erase DTC and verify the same DTC reoccure.
Go to "Terminal and Connector inspection" procedure.
In case there is symptom and wrong data with DTC
Check open,short or connector’s connection for HO2S.
Check the deterioration of HO2S performance.
Go to "Circuit Inspection" procedure.
This figures show the waveform of primary coil measured at terminal 1 of ignition coil at idle.is ON named DWELL and its normal voltage is below 0.5V.
The voltage at point ① is power supply of IG coil and it should be battery voltage
The signal at ② is the duration when power TR in ECM is ON named DWELL and its normal voltage is below 0.5V.
In case over 0.5V
Possible cause: Faulty power TR in ECM or poor ECM ground connection.
The waveform at ③ is surge voltage which occures at primary coil when power TR off and its normal voltage is over 320V.
In case when surge voltage is low
Possible cause: Open circuit in power line or poor ground connection.
