GDI ± Troubleshooting
13A-12
FAIL-SAFE FUNCTION REFERENCE TABLE
If the diagnosis system detects any sensor malfunction, the vehicle can be driven safely by using a default
control logic instead of the faulty sensors.
Defective part or
function
What to do when a sensor is defective
Air flow sensor (1) Disables lean-mixture combustion.
(2) Determines injector basic operating time and basic ignition timing according to map
value, which has been predetermined by throttle position sensor and crank angle
sensor signals.
Intake air temperature
sensor
Controls as the intake air temperature is 25_C.
Throttle position
sensor (1st channel)
(1) Disables lean-mixture combustion.
(2) Controls throttle valve opening angle by closed loop control by using the throttle position
sensor (2nd channel) signal.
(3) Disables the throttle valve opening angle control when the throttle position sensor
(2nd channel) signal is also defective.
Throttle position
sensor (2nd channel)
(1) Disables lean-mixture combustion.
(2) Controls throttle valve opening angle by closed loop control by using the throttle position
sensor (1st channel) signal.
(3) Disables the throttle valve opening angle control when the throttle position sensor
(1st channel) signal is also defective.
Engine coolant
temperature sensor
Controls as if the engine coolant temperature is 80_C. (Note that this control will continue
until the ignition switch is turned off even if the sensor signal return to normal.)
Camshaft position
sensor
Controls according to the conditions before a failure is detected.
Vehicle speed sensor (1) Disables lean-mixture combustion. However, if a predetermined time elapses at an
engine speed of 1,500 r/min or more, the lean-mixture combustion will return to normal.
(2) Disables lean-mixture combustion during engine idling.
Barometric pressure
sensor
Controls as if the barometric pressure is 101 kPa.
Detonation sensor Holds the ignition timing at that for standard petrol.
Injector (1) Disables lean-mixture combustion.
(2) Shuts down exhaust gas recirculation.
Abnormal combustion Disables lean-mixture combustion.
Communication line
with A/T-ECU
Disables ignition timing retard control (engine and transmission total control) during shift
change.
Alternator FR terminal Disables inhibition control of the alternator output according to electrical load (treats the
alternator as if it is conventional one).
Fuel pressure sensor (1) Controls as if the fuel pressure is 5 MPa (if there is open or short circuit).
(2) Turns off the fuel pump relay (if the fuel pressure is excessively high).
(3) Shuts off the fuel injection (If an excessively low pressure is detected or the engine
speed exceeds 3,000 r/min).
To Next Page
Loading...
