OPERATION FLOW
Tech Tips
Perform troubleshooting in accordance with the procedures below. The following is an outline of basic troubleshooting procedures. Confirm the troubleshooting procedures for the circuit you are working on before beginning troubleshooting.
VEHICLE BROUGHT TO WORKSHOP
NEXT |
CUSTOMER PROBLEM ANALYSIS
Ask the customer about the conditions and environment when the problem occurred.
NEXT |
INSPECT BATTERY VOLTAGE
Standard voltage |
---|
11 to 14 V |
If the voltage is below 11 V, recharge or replace the battery before proceeding.
NEXT |
SYMPTOM CONFIRMATION AND DTC (AND FREEZE FRAME DATA) CHECK
Visually check the wire harnesses, connectors and fuses for open and short circuits.
Warm up the engine to the normal operating temperature.
Confirm the problem symptoms and conditions, and check for DTCs.
Result | Proceed to |
---|---|
DTC is output | A |
DTC is not output | B |
B |
Go to step 6 |
A |
DTC CHART
Check the results obtained in the DTC check. Then find the output DTC in the DTC chart. Look at the "Trouble Area" column for a list of potentially malfunctioning circuits and / or parts.
NEXT |
Go to step 7 |
PROBLEM SYMPTOMS TABLE
Check the results obtained in the symptom confirmation. Then find the problem symptoms in the problem symptoms table. Look at the "Suspected Area" column for a list of potentially malfunctioning circuits and / or parts.
NEXT |
CIRCUIT INSPECTION OR PARTS INSPECTION
Confirm the malfunctioning circuit or part.
NEXT |
ADJUST, REPAIR OR REPLACE
Adjust, repair or replace the malfunctioning circuit or parts.
NEXT |
CONFIRMATION TEST
After the adjustment, repairs or replacement, confirm that the malfunction no longer exists. If the malfunction does not reoccur, perform a confirmation test under the same conditions and in the same environment as when the malfunction occurred the first time.
NEXT |
END |
CUSTOMER PROBLEM ANALYSIS
Tech Tips
In troubleshooting, confirm that the problem symptoms have been accurately identified. Preconceptions should be discarded in order to make an accurate judgment. To clearly understand what the problem symptoms are, it is extremely important to ask the customer about the problem and the conditions at the time the malfunction occurred.
Gather as much information as possible for reference. Past problems that seem unrelated may also help in some cases.
The 5 following questions are important points in the problem analysis:
What | Vehicle model, system name |
When | Date, time, occurrence frequency |
Where | Road conditions |
Under what conditions? | Running conditions, driving conditions, weather conditions |
How did it happen? | Problem symptoms |
SYMPTOM CONFIRMATION AND DIAGNOSTIC TROUBLE CODE
Tech Tips
The diagnostic system in the HILUX has various functions.
The first function is the Diagnostic Trouble Code (DTC) check. A DTC is a code stored in the ECU memory whenever a malfunction in the signal circuits to the ECU occurs. In a DTC check, a previous malfunction's DTC can be checked by a technician during troubleshooting.
Another function is the Input Signal Check, which checks if the signals from various switches are sent to the ECU correctly.
By using these functions, the problem areas can be narrowed down and troubleshooting will be more effective. Diagnostic functions are incorporated in the following system in the HILUX.
System | DTC Check (Normal Mode) |
DTC Check (Check Mode) |
Freeze Frame Data | Sensor Check/Test Mode (Input Signal Check) | Data List | Active Test | Customize Parameter |
---|---|---|---|---|---|---|---|
SFI System (for 1GR-FE) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 1KD-FTV, w/ DPF) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 1KD-FTV, w/ EGR Cooler) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 1KD-FTV, w/o EGR Cooler) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 2KD-FTV, w/ DPF) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 2KD-FTV, w/ EGR Cooler) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 2KD-FTV, w/o EGR Cooler) | ○ | ○ | ○ | - | ○ | ○ | - |
ECD System (for 5L-E) | ○ | ○ | ○ | - | ○ | ○ | - |
SFI System (for 1TR-FE) | ○ | ○ | ○ | - | ○ | ○ | - |
SFI System (for 2TR-FE) | ○ | ○ | ○ | - | ○ | ○ | - |
Charging System (for 1GR-FE) | - | - | - | - | - | - | - |
Charging System (for 1KD-FTV) | - | - | - | - | - | - | - |
Charging System (for 2KD-FTV) | - | - | - | - | - | - | - |
Charging System (for 5L-E) | - | - | - | - | - | - | - |
Charging System (for 1TR-FE) | - | - | - | - | - | - | - |
Charging System (for 2TR-FE) | - | - | - | - | - | - | - |
Automatic Transmission System (for A340E) | ○ | ○ | ○ | - | ○ | ○ | - |
Automatic Transmission System (for A340F, 2KD-FTV) | ○ | ○ | ○ | - | ○ | ○ | - |
Electronic Controlled Automatic Transmission System (for A340F, 1KD-FTV) | ○ | ○ | ○ | - | ○ | ○ | - |
Automatic Transmission System (for A343E) | ○ | ○ | ○ | - | ○ | ○ | - |
Automatic Transmission System (for A343F) | ○ | ○ | ○ | - | ○ | ○ | - |
Electronic Controlled Automatic Transmission System (for A750E) | ○ | ○ | ○ | - | ○ | ○ | - |
Automatic Transmission System (for A750F, for 1KD-FTV) | ○ | ○ | ○ | - | ○ | ○ | - |
Electronic Controlled Automatic Transmission System (for A750F, for 1GR-FE) | ○ | ○ | ○ | - | ○ | ○ | - |
Anti-lock Brake System | ○ | - | ○ | ○ | ○ | ○ | - |
Anti-lock Brake System (w/ Rear Differential Lock) | ○ | - | ○ | ○ | ○ | ○ | - |
Vehicle Stability Control System | ○ | - | ○ | ○ | ○ | ○ | - |
Air Conditioning System (for Manual Air Conditioning System) | - | - | - | - | - | - | - |
Air Conditioning System (for Cold Area) | - | - | - | - | - | - | - |
Air Conditioning System (Automatic Air Conditioning System) | ○ | - | - | - | ○ | - | - |
Airbag System | ○ | ○ | - | - | ○ | - | - |
Seat Belt Warning System | - | - | - | - | - | - | - |
Theft Deterrent System | - | - | - | - | - | - | - |
Engine Immobiliser System | ○ | - | - | - | ○ | ○ | - |
Cruise Control System | ○ | - | - | - | ○ | - | - |
Lighting System | - | - | - | - | - | - | - |
Wiper and Washer System | - | - | - | - | - | - | - |
Power Door Lock Control System | - | - | - | - | - | - | ○ |
Power Door Lock Control System (for 2 Step Unlock Function) | - | - | - | - | - | - | ○ |
Wireless Door Lock Control System (for Built-in Type Door Control Receiver) | - | - | - | - | - | - | ○ |
Wireless Door Lock Control System (for Non-built-in Type Door Control Receiver) | - | - | - | - | - | - | - |
Meter / Gauge System | - | - | - | - | ○ | ○ | ○ |
Audio and Visual System (for Radio Receiver Type) | - | - | - | - | - | - | - |
Audio and Visual System (for Radio and Display Type) | ○ | - | - | - | - | - | - |
Navigation System | ○ | - | - | - | - | - | - |
Rear View Monitor System (for Radio and Display Type) | ○ | - | - | - | - | - | - |
Rear View Monitor System (for Navigation Receiver Type) | ○ | - | - | - | - | - | - |
Horn System | - | - | - | - | - | - | - |
Power Window Control System | - | - | - | - | - | - | - |
Window Defogger System | - | - | - | - | - | - | - |
Power Mirror Control System | - | - | - | - | - | - | - |
Front Power Seat Control System | - | - | - | - | - | - | - |
Seat Heater System | - | - | - | - | - | - | - |
CAN Communication System (w/ VSC) | - | - | - | - | - | - | - |
In the DTC check, it is very important to determine whether the problem indicated by the DTC is either: 1) still occurring, or 2) occurred in the past but has since returned to normal. In addition, the DTC should be compared to the problem symptom to see if they are related. For this reason, DTCs should be checked before and after confirmation of symptoms (i.e., whether or not problem symptoms exist) to determine current system conditions, as shown in the flowchart below.
Never skip the DTC check. Failing to check DTCs may, depending on the case, result in unnecessary troubleshooting for systems operating normally or lead to procedures not related to the problem. Follow the procedures listed in the flowchart in the correct order.
The following flowchart shows how to proceed with troubleshooting using the DTC check. Directions from the flowchart will indicate how to proceed either to DTC troubleshooting or to the troubleshooting of each problem symptom.
DTC CHECK
NEXT |
MAKE A NOTE OF DTCS DISPLAYED AND THEN CLEAR MEMORY
NEXT |
SYMPTOM CONFIRMATION
Result | Proceed to |
---|---|
No symptoms exist | A |
Symptoms exist | B |
B |
Go to step 5 |
A |
SIMULATION TEST USING SYMPTOM SIMULATION METHODS
NEXT |
DTC CHECK
Result | Proceed to |
---|---|
DTC is not output | A |
DTC is output | B |
B |
TROUBLESHOOTING OF PROBLEM INDICATED BY DTC |
A |
SYMPTOM CONFIRMATION
Result | Proceed to |
---|---|
No symptoms exist | A |
Symptoms exist | B |
If a DTC was displayed in the initial DTC check, the problem may have occurred in a wire harness or connector in that circuit in the past. Check the wire harness and connectors.
B |
SYSTEM NORMAL |
A |
TROUBLESHOOTING OF EACH PROBLEM SYMPTOM |
The problem is still occurring in a place other than the diagnostic circuit (the DTC displayed first is either for a past problem or a secondary problem).
SYMPTOM SIMULATION
Tech Tips
The most difficult case in troubleshooting is when no problem symptoms occur. In such a case, a thorough problem analysis must be carried out. A simulation of the same or similar conditions and environment in which the problem occurred in the customer's vehicle should be performed. No matter how much skill or experience a technician has, troubleshooting without confirming the problem symptoms will lead to important repairs being overlooked and mistakes or delays.
VIBRATION METHOD: When a malfunction seems to occur as a result of vibration.
PART AND SENSOR
Apply slight vibration with a finger to the part of the sensor suspected to be the cause of the problem, and check whether or not the malfunction occurs.
Note
Applying strong vibration to relays may open relays.
CONNECTORS
Slightly shake the connector vertically and horizontally.
WIRE HARNESS
Slightly shake the wire harness vertically and horizontally.
Tech Tips
The connector joint and fulcrum of the vibration are the major areas that should be checked thoroughly.
HEAT METHOD: When a malfunction seems to occur as a result of heat.
Heat the component that is the possible cause of the malfunction with a hair dryer or similar device. Check if the malfunction occurs.
Note
Do not heat to more than 60°C (140°F). Exceeding this temperature may damage components.
Do not apply heat directly to the parts in an ECU.
WATER SPRINKLING METHOD: When a malfunction seems to occur on a rainy day or in high humidity.
Sprinkle water onto the vehicle and check if the malfunction occurs.
Note
Never sprinkle water directly into the engine compartment. Indirectly change the temperature and humidity by spraying water onto the front of the radiator.
Never apply water directly onto the electronic components.
Tech Tips
If the vehicle has or had a water leakage problem, the leakage may have damaged ECUs or connections. Look for evidence of corrosion or short circuits. Proceed with caution during water tests.
HIGH ELECTRICAL LOAD METHOD: When a malfunction seems to occur when the electrical load is excessive.
Turn on the heater blower, headlights, rear window defogger and all other electrical loads. Check if the malfunction occurs.
DIAGNOSTIC TROUBLE CODE CHART
Look for output Diagnostic Trouble Codes (DTCs) (from the DTC checks) in the appropriate section's Diagnostic Trouble Code Chart. Use the chart to determine the trouble area and the proper inspection procedure. A description of each of the chart's columns is below.
Item | Description |
---|---|
DTC No. | Indicates the diagnostic trouble code. |
Detection Item | Indicates the system or details of the problem. |
Trouble Area | Indicates the suspected areas of the problem. |
See Page | Indicates where the inspection procedures for each circuit can be found, or gives instructions for checking and repairs. |
PROBLEM SYMPTOMS TABLE
When a "Normal" code is output during a DTC check but the problem is still occurring, use the problem symptoms table. The suspected areas (circuits or parts) for each problem symptom are in the table. The suspected areas are listed in order of probability. A description of each of the chart's columns is below.
Tech Tips
In some cases, the problem is not detected by the diagnostic system even though a problem symptom is present. It is possible that the problem is occurring outside the detection range of the diagnostic system, or that the problem is occurring in a completely different system.
Item | Description |
---|---|
Symptom | - |
Suspected Area | Indicates the circuit or part which needs to be checked. |
See Page | Indicates where the flowchart for each circuit is located. |
CIRCUIT INSPECTION
A description of the main areas of each circuit inspection is below.
Item | Description |
---|---|
Description | The major role of the circuit, its operation and its component parts are explained. |
DTC No., DTC Detection Condition, Trouble Area | Indicates the diagnostic trouble codes, diagnostic trouble code detection conditions, and trouble areas of a problem. |
Wiring Diagram | This shows a wiring diagram of a circuit. Use this diagram together with an ELECTRICAL WIRING DIAGRAM to thoroughly understand the circuit. |
Inspection Procedures | Use the inspection procedures to determine if the circuit is normal or abnormal. If abnormal, use the inspection procedures to determine whether the problem is located in the sensors, actuators, wire harnesses or ECU. |
Indicates the condition of the connector of the ECU during the check | Connector being checked is connected. Connections of tester are indicated by (+) or (-) after the terminal name. Connector being checked is disconnected. For illustrations of inspections between a connector and body ground, information about the body ground is not shown in the illustration. |