When troubleshooting obd ii (on-board diagnostics) vehicles, the intelligent tester (complying with sae j1987) must be connected to the dlc3 (data link connector 3) of the vehicle. Various data in the vehicle's ecm (engine control module) can be then read.
Obd ii regulations require that the vehicle's on-board computer illuminate the mil (malfunction indicator lamp) on the instrument panel when the computer detects a malfunction in:
In addition, if the applicable dtcs (diagnostic trouble codes) prescribed by sae j2012 are not recorded on 3 consecutive trips, the mil turns off automatically but the dtcs remain recorded in the ecm memory.
To
check dtcs, connect the intelligent tester to the
dlc3. The tester displays dtcs, freeze frame data, and
a variety of the engine data. The dtcs and freeze frame
data can be erased with the tester (see page es-35).
In order to enhance obd function on vehicles and develop the off-board diagnosis system, can (controller area network) communication is introduced in this system. It minimizes the gap between technician skills and vehicle technology. Can is a network, which uses a pair of data transmission lines, spanning multiple computers and sensors. It allows high speed communication between the systems and simplifies the wire harness connection.
Since this system is equipped with the can communication, connecting the can vim (vehicle interface module) to the intelligent tester is necessary to display any information from the ecm. (Also the communication between the intelligent tester and the ecm uses can communication signals.) When confirming the dtcs and any data of the ecm, connect the can vim between the dlc3 and the intelligent tester.
The diagnosis system operates in normal mode during normal vehicle use. In normal mode, 2 trip detection logic is used to ensure accurate detection of malfunctions. Check mode is also available as an option for technicians. In check mode, 1 trip detection logic is used for simulating malfunction symptoms and increasing the system's ability to detect malfunctions, including intermittent problems (intelligent tester only) (see page es-38).
When a malfunction is first detected, the malfunction is temporarily stored in the ecm memory (1st trip). If the same malfunction is detected during the next subsequent drive cycle, the mil is illuminated (2nd trip).
Freeze frame data records the engine conditions (fuel system, calculated engine load, engine coolant temperature, fuel trim, engine speed, vehicle speed, etc.) When malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
Caution:
*: Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the ignition switch, any other switches or the doors.
If the result is not as specified, the dlc3 may have a malfunction. Repair or replace the harness and connector.
Hint:
The dlc3 is the interface prepared for reading various data from the vehicle's ecm. After connecting the cable of the intelligent tester to the can vim, turn the ignition switch on and turn the tester on. If a communication failure message is displayed on the tester screen (on the tester: unable to connect to vehicle), a problem exists in either the vehicle or tester. In order to identify the location of the problem, connect the tester to another vehicle.
If communication is normal: inspect the dlc3 on the original vehicle.
If communication is still not possible: the problem is probably in the tester itself. Consult the service department listed in the instruction manual.
Standard battery voltage: 11 to 14 v
If the voltage is below 11 v, replace or recharge the battery before proceeding.
Hint:
If the mil is not illuminated when the ignition switch is first turned on, check the mil circuit (see page es-386).
For the vehicle, using the intelligent tester allows readiness codes corresponding to all dtcs to be read.
When diagnosis (normal or malfunctioning) has been complete, readiness codes are set. Select the following menu items on the intelligent tester: enhanced obd ii / monitor status.
Audio system
Operations such as listening to audio, using the hands-free
phone, confirming vehicle information and changing audio system
settings are started by using the following buttons.
Audio system operation buttons
“Audio” button
Display the “select audio source” screen or audio top s ...
Security indicator light circuit
Description
When the transponder key is registered, the transponder key ecu indicates the
key registration condition
by lighting up, blinking or turning off the security indicator.
Wiring diagram
Inspection procedure
Perform active test by intelligent tester (security indicator light)
...
Source voltage drop
Description
The srs is equipped with a voltage-increase circuit (dc-dc converter) in the
center airbag sensor in
case the source voltage drops.
When the source voltage drops, the voltage-increase circuit (dc-dc converter)
functions to increase the
voltage of the srs to a normal working lev ...