CODE NO. P1576:
Torque Control Fail (Air Flow Sensor) <4J1> CODE NO. P1577: Torque Control Fail
(Manifold Absolute Pressure Sensor) <4J1> CODE NO. P1578: Torque Control Fail (Barometric
Pressure Sensor) <4J1> CODE NO. P1579: Torque Control Fail (Engine Coolant Temperature
Sensor) <4J1>
DIAGNOSIS CODE SET CONDITIONS
This diagnosis code will be set when the engine-ECU determines that is defective according
to the following conditions. Code No. P1576
The air flow sensor output voltage is abnormal for two seconds.
The difference between the volumetric efficiency (actual value) which is based on
the air flow sensor value and that which is based on the throttle position sensor exceeds a
predetermined value.
note
This diagnosis code may be set before the engine-ECU determines that the air flow sensor
system is defective.
Code No. P1577
The manifold absolute pressure sensor output voltage is abnormal for two seconds.
note
This diagnosis code may be set before the engine-ECU determines that the manifold absolute
pressure sensor system is defective.
Code No. P1578
The barometric pressure sensor output voltage is abnormal for 12 seconds.
note
This diagnosis code may be set before the engine-ECU determines that the barometric pressure
sensor system is defective.
Code No. P1579
The engine coolant temperature sensor output voltage is abnormal for two seconds.
note
This diagnosis code may be set before the engine-ECU determines that the engine coolant
temperature sensor system is defective.
Failed engine coolant temperature sensor <Code No. P1579>
Open/short circuit or harness damage in air flow sensor circuit or loose
connector contact.
Malfunction of the engine-ECU.
DIAGNOSIS PROCEDURE
STEP 1. Check the MPI system diagnosis code.
Using M.U.T.-III, perform MPI system diagnosis code (Refer to GROUP 13C - Troubleshooting,
Diagnosis Function ).
Q.
Is any diagnosis code set?
Repair the MPI system (Refer to GROUP 13C - Troubleshooting, Inspection
Chart for Diagnosis Code ). Then go to Step 3.
Go to Step 2
STEP 2. Read the diagnosis code.
(1)Use the M.U.T.-III, erase the diagnosis code of the cruise control system.
(2)Turn the ignition switch to the "ON" position, and press the cruise control ON/OFF
switch to turn the cruise control system to ON (the cruise control indicator lamp <standard meter> or
the cruise control display screen <high contrast meter> is turned on).
(3)After turning the cruise control system to ON, when 2 minutes or more has elapsed
without operating the cruise control switches, read the diagnosis code of the cruise control
system (Refer to ).
Q.
Is diagnosis code No. P1576, P1577, P1578 or P1579 set?
Replace the engine-ECU (Refer to GROUP 13C - Engine-ECU ).
Then go to Step 3.
It can be assumed that this malfunction is intermittent (Refer to GROUP 00 - How
to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunction ).
STEP 3. Read the diagnosis code.
(1)Use the M.U.T.-III, erase the diagnosis code of the cruise control system.
(2)Turn the ignition switch to the "ON" position, and press the cruise control ON/OFF
switch to turn the cruise control system to ON (the cruise control indicator lamp <standard meter> or
the cruise control display screen <high contrast meter> is turned on).
(3)After turning the cruise control system to ON, when 2 minutes or more has elapsed
without operating the cruise control switches, read the diagnosis code of the cruise control
system (Refer to ).
Q.
Is diagnosis code No. P1576, P1577, P1578 or P1579 set?