The waveforms and amplitudes displayed differ slightly depending on the vehicle

5 V/DIV

20 ms./DIV

20 ms./DIV

IGT Ground +

IGF Ground +

5. WAVEFORM 5

Crankshaft position sensor and Camshaft position sensor:

ECM Terminal Names

CH1: Between G2+ and G2-CH2: Between NE+ and NE-

Tester Ranges

5 V/DIV., 20 ms./DIV.

Conditions

The wavelength becomes shorter as the engine rpm increases.

WAVEFORM 6

Igniter IGT signal (from ECM to igniter) and Igniter

IGF signal (from igniter o ECM):

ECM Terminal Names

Between IGT (1 to 4) and E1

Between IGF1 and E1

Tester Ranges

2 V/DIV., 20 ms./DIV.

Conditions

Idling

HINT:

The wavelength becomes shorter as the engine rpm

increases.

7. WAVEFORM 7

Purge VSV:

ECM Terminal Names

Between PRG and E1

Tester Ranges

5 V/DIV., 50 ms./DIV.

Conditions

Idling

HINT:

If the waveform is not similar to the illustration, check the

waveform again after idling for 10 minutes or more.

8. WAVEFORM 8

Vehicle speed signal:

ECM Terminal Names

Between SPD and E1

Tester Ranges

2 V/DIV., 20 ms./DIV.

Conditions

Driving at 12 mph (20 km/h)

HINT:

The wavelength becomes shorter as the vehicle speed

increases.

9. WAVEFORM 9

Throttle actuator positive terminal:

ECM Terminal Names

Between M+ and ME01

Tester Ranges

5 V/DIV., 1 ms./DIV.

Conditions

Idling with warm engine

HINT:

The duty ratio varies depending on the throttle actuator operation.

A093274E13

A093275E12

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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