13A-22
MPI – TROUBLESHOOTING
Inspect the air temperature
sensor on its own (Ref: P13A-29)
Check connector B-34
Measure at the air temperature
sensor connector B-34
• Undo the connector and
measure on the harness side
(1) Resistance across earth at 2
OK: Less than 2Ω
(2) Voltage across earth at 1
(Ignition switch: ON)
OK: 4.9~5.1V
Go on to the next page
Replace the air temperature
sensor
Temporary malfunction (Ref
Section 00: Dealing with
temporary malfunctions)
Measure at the engine ECU
connector C-51
• Measure the voltage at the
engine ECU terminal
• Ignition switch: ON
•Voltage across earth at 96
OK: 4.5~4.9V
Replace the engine ECU
Check that the problem has been
solved
Inspect the harness between the
air temperature sensor and the
engine ECU
• Check if the earth wire is cut
or damaged
Check connector: C-50
Inspect the harness between the
air temperature sensor and the
engine ECU and repair it if
necessary.
• Check if the output wire is cut
Check connector: C-51
Temporary malfunction (Ref
Section 00: Dealing with
temporary malfunctions)
Check connector: C-51
Check that the problem has been
solved
Replace the engine ECU
Inspect the harness between the
air temperature sensor and the
engine ECU and repair it if
necessary.
• Check if the output wire is cut
OK
NG
(1) NG
(2) NG
NG
OK
OK
NG
NG
NG
OK
NG
OK
OK
OK
NG
NG
NG
NG
NG
OK
Repair
Repair
Repair
Repair
Repair
Air temperature sensor system Probable causes of the malfunction
The air temperature sensor controls the temperature inside the inlet
manifold, and compensates for any burning of fuel.
• Malfunction of the air temperature sensor.
• Circuit break, short circuit or a faulty connection in
the air temperature sensor circuit.
• Malfunction of the engine ECU.
Inspection procedure 38
OK
NG
Repair
