PROBLEM SYMPTOMS TABLE




warning A high-tension voltage is flowing between the engine-ECU and the injectors while the engine is running. Handle them carefully to avoid receiving electric shocks from the voltage.
Trouble symptom
Inspection procedure
Reference page
Communication with Engine-ECU is Not Possible
1

Starter System
2

Engine-ECU Power Supply, Engine Control Relay, Ignition Switch-IG1 System
3

Boost Pressure Sensor System
4

Intake Air Temperature Sensor System
5

Air Flow Sensor System
6

Engine Coolant Temperature Sensor System
7

Fuel Temperature Sensor System
8

Crank Angle Sensor System
9

Camshaft Position Sensor System
10

Accelerator Pedal Position Sensor (main) System
11

Accelerator Pedal Position Sensor (sub) System
12

No. 1 Injector System
13

No. 2 Injector System
14

No. 3 Injector System
15

No. 4 Injector System
16

Variable Geometry Solenoid Valve System
17

EGR Control Solenoid Valve System
18

EGR Cooler Solenoid Valve System
19

Intake Air Control Flap System
20

Alternator System
21

Glow System
22

Fuel Pump System
23

A/C Compressor Relay System
24

Clutch Switch System
25

Stop Lamp Switch System <Vehicles with Auto-cruise Control System>
26

Engine Oil Pressure Switch System
27


INSPECTION CHART FOR TROUBLE SYMPTOMS
Trouble symptom
Probable cause
Remedy
Reference page
Engine warning lamp
The engine warning lamp does not illuminate right after the ignition switch is turned the "ON" position

  • Failed engine warning lamp


  • Check the combination meter

Refer to GROUP 54A - Combination Meter - Check Chart for Trouble Symptoms

  • Open circuit in combination meter circuit


  • Check the combination meter circuit

Engine warning lamp
The engine warning lamp remains illuminating and never goes out

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Short circuit in combination meter circuit


  • Check the combination meter

Refer to GROUP 54A - Combination Meter - Check Chart for Trouble Symptoms

  • Check the combination meter circuit

Starting
Starting impossible (Starting not possible)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injection System , , ,

  • Contamination (water, kerosene, etc.) in fuel, and repair if necessary

-

  • Failed glow system


  • Check the glow system

Refer to Inspection Procedure - Glow System

  • Failed compression pressure


  • Check the compression pressure

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Starting
Poor start ability when engine is cold (Poor starting)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to inspection Procedure - Injector System , , ,

  • Contamination (water, kerosene, etc.) in fuel, and repair if necessary

-

  • Failed glow system


  • Check the glow system

Refer to Inspection Procedure - Glow System

  • Failed engine oil viscosity


  • Check the engine oil viscosity, and replace if necessary

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Starting
Poor start ability when engine is both cold and warm (Poor starting)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to inspection Procedure - Injector System , , ,

  • Contamination (water, kerosene, etc.) in fuel, and repair if necessary

-

  • Failed compression pressure


  • Check the compression pressure

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idlimg stability (Improper idling)
Idle speed is low when engine is cold (Improper idling speed)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idlimg stability (Improper idling)
Idle speed is high (Improper idling speed)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idlimg stability (Improper idling)
Idle speed is low (Improper idling speed)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idlimg stability (Improper idling)
Idle speed is unstable (Rough idling, hunting)

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Contamination (water, kerosene, etc.) in fuel, and repair if necessary

-

  • Failed glow system


  • Check the glow system

Refer to Inspection Procedure - Glow System

  • Failed EGR system


  • Check the EGR system

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idling stability (Engine stalls)
Engine stops soon after starting

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed engine-ECU


  • Replace the engine-ECU

-
Idling stability (Engine stalls)
Engine stops during idling

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed EGR system


  • Check the EGR system

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Driving
Engine output is too low

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Contamination (water, kerosene, etc.) in fuel, and repair if necessary

-

  • Failed EGR system


  • Check the EGR system

-

  • Failed turbocharger


  • Check the boost pressure control system and turbocharger, and repair if necessary

-

  • Failed compression pressure


  • Check the compression pressure

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Driving
Abnormal engine knocking occurs

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed engine-ECU


  • Replace the engine-ECU

-
Driving
Abnormally black smoke

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed EGR system


  • Check the EGR system

-

  • Failed turbocharger


  • Check the boost pressure control system and turbocharger, and repair if necessary

-

  • Failed air cleaner element


  • Check the air cleaner element, and replace if necessary

-

  • Catalytic converter deteriorated


  • Check the catalytic converter, and replace if necessary

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Driving
Abnormally white smoke

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Oil loss via the piston ring


  • Check the piston ring, and replace if necessary

-

  • Oil loss via the valve guides


  • Check the valve guides, and replace if necessary

-

  • Failed engine-ECU


  • Replace the engine-ECU

-
Driving
Hunting occurs while driving

  • Failed engine control system


  • Check the output diagnosis code

Refer to Inspection Chart for Diagnosis Code

  • Check the data list

Refer to Data List Referrence Table

  • Check the actuator test

Refer to Actuator Test Reference Table

  • Failed fuel system


  • Check the fuel high pressure and fuel supply line, and repair if necessary

-

  • Check the fuel injector

Refer to Inspection Procedure - Injector System , , ,

  • Failed EGR system


  • Check the EGR system

-

  • Failed engine-ECU


  • Replace the engine-ECU

-