Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Diagnosis system / Check dlc3
Toyota Corolla (E120): Check dlc3
The vehicle’s ecm uses the iso 9141–2 for communication protocol. The terminal arrangement of the dlc3 complies with sae j1962 and matches the iso 9141–2 format.


Hint
: if the display shows unable to connect to vehicle when you have connected the cable of the obd ii scan tool or the hand–held tester to the dlc3, turned the ignition switch on and operated the scan tool, there is a problem on the vehicle side or tool side.
- If the communication is normal when the tool is connected to another vehicle, inspect the dlc3 on the original vehicle.
- If the communication is still impossible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the service department listed in the tool’s instruction manual.
Inspect battery voltage
Battery voltage: 11 to 14 v
If voltage is below 11 v, recharge the battery before proceeding.
Check mil
- The mil comes on when the ignition switch is turned on
and the engine is not running.
Hint
: if the mil is not illuminated, troubleshoot the mil circuit .
- when the engine is started, the mil should go off. If the mil remains on, it means that the diagnosis system has detected a malfunction or abnormality in the system.
Other materials:
Circuit description
The actuator motor is operated by signals from the cruise control ecu assy.
Acceleration and deceleration
signals are transmitted by changes in the duty ratio (see below).
Duty ratio:
the duty ratio is the ratio of the period of continuity in one cycle. For
example, if a is the period of co ...
Using the radio (Multimedia system)
Radio operation
Select “AM” or “FM” on the audio source selection screen to begin listening
to the radio.
Audio control screen
Pressing the “AUDIO” button displays the audio control screen from any screens
of the selected source.
1 Audio source selection screen appears
2 Preset ...
Inspection procedure
1 Check d squib circuit(airbag sensor assy center – horn button
assy)
Disconnect the negative (–) terminal cable from the battery,
and wait at least for 90 seconds.
disconnect the connectors between the horn button assy
and the airbag sensor assy center.
for the oran ...


