Trouble Diagnosis by Service Support

Trouble Diagnosis by Service Support Trouble diagnosis by service support

Trouble diagnosis by service support is a systematic method for confirming problems that occur due to function deficiencies of the engine control system, and is the starting point for all mechanical operability complaint diagnosis.By correctly utilizing this diagnosis step, diagnosis time is shortened and replacement of non-defective parts is prevented.

Test explanation

4. When a diagnostic trouble code is detected, see "Proceed to the relevant DTC diagnosis" and go to the appropriate diagnostic trouble code diagnosis.When multiple diagnostic trouble codes have been detected, as long as there is no other indication within the diagnostic steps, start diagnosis from the diagnostic trouble code with the smallest number.

Cautions in trouble diagnosis by service support

important: •When there are no complaints about mechanical operability, do not perform this diagnosis step as long as there are no other indications in other items. •Before beginning diagnosis, check the service information. •As long as there is no other indication within the diagnostic steps, do not delete the diagnostic trouble codes. •When an abnormality is found in the engine start system, see "Electrical System" in "Engine" of the

Service Manual. •The battery should be fully charged. •The condition of the battery cable should be normal and it should be securely connected. •The ground of the ECM should be securely connected in the correct position.

Step Action

1

1. Turn the key switch "ON". 2. Confirm the diagnostic trouble code.

*Make sure to confirm this as there are some diagnostic trouble codes in which ELEC. PROBLEM does not display.

3. Did a diagnostic trouble code display? 2 Turn the key switch to the "START" position. Did the starter operate? 3 Turn the key switch to the "START" position. Did the engine start?

4 Check that no diagnostic trouble codes have been detected. Was a diagnostic trouble code detected?

5 1. Check whether there are any of the following problems. ・ Engine stalling ・ Engine hunting, rough idling ・ Engine output deficiency, revving problem, engine hesitation ・ Great deal of white smoke in exhaust gas ・ Great deal of black smoke in exhaust gas ・ Idling speed cannot be adjusted ・ Idling speed does not go down Was a problem detected? Value Yes No

Go to relevant diagnostic trouble code display. Go to step 2.

- Go to step 3.

- Go to step 4. Go to "Checking the Start Circuit System". Go to "Checking the Start System".

Go to relevant diagnostic trouble code diagnosis. Go to step 5.

Go to relevant problem phenomenon diagnosis. System normal