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:
Terminals of ecu
1. Inspect tvip ecu
Inspect the ecu–b, dome and ecu–ig fuses.
disconnect the tvip ecu connector, and the continuity and voltage of
check each terminal of the disconnected
connector.
Standard:
If the result is not as specified, the vehicle’s side may malfunction.
Reco ...
Circuit description
The intake air temperature (iat) sensor, mounted on the mass
air flow (maf) sensor, monitors the intake air temperature. The
iat sensor has a thermistor that varies its resistance depending
on the temperature of the intake air. When the air temperature
is low, the resistance in the thermisto ...
Check open circuit
For the open circuit in the wire harness in fig. 1, Perform
a resistance check in step (b) or a voltage check in step
(c) to locate the section.
Check the resistance.
Disconnect connectors a and c and measure the
resistance between them.
Resistance: 1 Ω or les ...


