Toyota Corolla (E120) 2002–2008 Repair Manual / Diagnostics / Sfi system / Intake air temperature circuit / Inspection procedure
Toyota Corolla (E120): Inspection procedure
Hint
:
- if different dtcs related to different systems that have terminal e2 as the ground terminal are output simultaneously, terminal e2 may be open.
- Read freeze frame data using the hand-held tester or the obd ii scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air–fuel ratio was lean or rich, etc. At the time of the malfunction.
1 Read value of hand–held tester or obd ii scan tool(intake air temperature)
- Connect the hand–held tester or the obd ii scan tool to the dlc3.
- turn the ignition switch on and push the hand–held tester or the obd ii scan tool main switch on.
- select the item ”diagnosis / enhanced obd ii / data list / all / intake air” and read its value displayed on the hand–held tester or the obd ii scan tool.
Temperature: same value as the actual intake air temperature.
Result:

Hint
:
- if there is an open circuit, the hand–held tester or the obd ii scan tool indicates –40 °C (–40°f).
- If there is a short circuit, the hand–held tester or the obd ii scan tool indicates 140 °C (284°f) or more.


2 Read value of hand–held tester or obd ii scan tool(check for open in wire harness)

- Disconnect the m1 mass air flow sensor connector
- connect terminals tha and e2 of the mass air flow sensor wire harness side connector.
- turn the ignition switch on.
- select the item ”diagnosis / enhanced obd ii /
data list / all / intake air” and read its value displayed
on the hand–held tester or the obd ii scan tool.
Temperature value: 140 °C (284°f) or more
- reconnect the mass air flow sensor connector.



3 Read value of hand–held tester or obd ii scan tool(check for open in ecm)

- Disconnect the m1 mass air flow sensor connector.
- connect the terminals tha and e2 of the e3 ecm connector.
Hint
: before checking, do a visual and contact pressure check on the ecm connector.
- turn the ignition switch on.
- select the item ”diagnosis / enhanced obd ii /
data list / all / intake air” and read its value displayed
on the hand–held tester or the obd ii scan tool.
Temperature value: 140 °C (284°f) or more
- reconnect the mass air flow sensor connector.



Confirm good connection at ecm. If ok, replace ecm
4 Read value of hand–held tester or obd ii scan tool(check for short in wire harness)

- Disconnect the m1 mass air flow sensor connector.
- turn the ignition switch on.
- select the item ”diagnosis / enhanced obd ii /
data list / all / intake air” and read its value displayed
on the hand–held tester or the obd ii scan tool.
Temperature value: –40 °C (–40°f)
- reconnect the mass air flow sensor connector.


5 Read value of hand–held tester or obd ii scan tool(check for short in ecm)

- Disconnect the e3 ecm connector.
- turn the ignition switch on.
- select the item ”diagnosis / enhanced obd ii /
data list / all / intake air” and read its value displayed
on the hand–held tester or the obd ii scan tool.
Temperature value: –40 °C (–40°f)
- reconnect the ecm connector.



Replace ecm
Other materials:
Setting the tire pressure
(vehicles with a tire pressure
warning system)
In the following situations, it will
be necessary to perform the tire
inflation pressure setting procedure
of the tire pressure warning
system.
When the specified tire inflation
pressure has changed,
such as due to carried load,
etc.
When the tire inflation pressure
is changed such as
when t ...
Wireless remote control
(if equipped)
The keys are equipped with the
following wireless remote control:
Vehicles without a smart key
system
Locks the doors
Unlocks the doors
Opens the windows*1 and
moon roof*1, 2
Opens the trunk
Sounds the alarm
Vehicles with a smart key system
Locks the doors
Unlocks the doors
Opens the ...
Do-it-yourself service precautions
If you perform maintenance by yourself, be sure to follow the correct procedure
as given in these sections.
CAUTION
The engine compartment contains many mechanisms and fluids that may move suddenly,
become hot, or become electrically energized. To avoid death or serious injury,
observe t ...


