Code No.B1131 Starter setting circuit fail


caution
  • Use caution that the cooling fan becomes activated when the forced power supply output of M.U.T.-III is performed while the engine-ECU connector is disconnected. (Fail-safe for ETACS-ECU)
  • When replacing the ECU, always check that the communication circuit is normal.

DIAGNOSTIC FUNCTION



JUDGEMENT CRITERIA


Check Conditions
  • After OSS-ECU activation
Judgment Criterion
  • When the following conditions are met:

  1. When the starter setting signal is ON, the starter setting circuit voltage is less than 1.5 V.
  2. When the starter setting signal is OFF, the circuit voltage is 3.5 V or more.

PROBABLE CAUSES



  • Damaged wiring harness or connector (short to earth or short to power supply in STO line or STOE line)
  • Malfunction of OSS-ECU
  • ETACS-ECU malfunction
  • Malfunction of engine-ECU
  • Malfunction of AS&G-ECU

DIAGNOSIS PROCEDURE

STEP 1. Check of short circuit in STO line between OSS-ECU connector and ETACS-ECU connector

Q. Is the check result normal?
Go to Step 2
Repair the connector(s) or wiring harness.

STEP 2. Check of short circuit in STOE line between ETACS-ECU connector and engine-ECU connector

Q. Is the check result normal?
YES <Vehicles with AS&G> : Go to Step 3
YES <Vehicles without AS&G> : Go to Step 4
NO : Repair the connector(s) or wiring harness.

STEP 3. Check of short circuit in STOE line between ETACS-ECU connector and AS&G-ECU connector

Q. Is the check result normal?
Go to Step 4
Repair the connector(s) or wiring harness.

STEP 4. Voltage measurement at engine-ECU connector (STOE terminal)
(1)Disconnect the engine-ECU connector, and measure at the wiring harness side. For vehicles with AS&G, also disconnect AS&G-ECU.
(2)Using the M.U.T.-III, set the forced power supply output to other than "IG-ST".(Refer to .)
(3)Measure the voltage between the engine-ECU connector (STOE terminal) and body earth.
OK: 1 V or less
(4)Using the M.U.T.-III, set the forced power supply output to "IG-ST".(Refer to .)
(5)Measure the voltage between the engine-ECU connector (STOE terminal) and body earth.
OK: System voltage

Q. Is the check result normal?
YES <vehicles with AS&G> : Go to Step 5
YES <vehicles without AS&G> : Go to Step 8
NO :

STEP 5. M.U.T.-III other system data list
Check the engine-ECU data list.
(1)Disconnect the AS&G-ECU connector.
(2)Using the M.U.T.-III, perform the forced power supply output.

<PETROL VEHICLE>
State of forced power supply output
 Item No.
 Check item
 Display
IG-ST
 79
 Cranking signal
(Ignition switch-ST)
 ON
Other than IG-ST
 OFF

<DIESEL VEHICLE>
State of forced power supply output
 Item No.
 Check item
 Display
IG-ST
 40
 Starter switch
 ON
Other than IG-ST
 OFF
OK: Depending on the state of forced power supply output, the display is turned ON/OFF.

Q. Is the check result normal?
Go to Step 6
Replace the engine-ECU and register the chassis number and key codes [Refer to GROUP 00 - How to Perform Chassis Number (Chassis No.) Writing ].

STEP 6. M.U.T.-III other system data list
Check the AS&G-ECU data list.
(1)Disconnect the engine-ECU connector.
(2)Using the M.U.T.-III, perform the forced power supply output.
State of forced power supply output
 Item No.
 Check item
 Display
IG-ST
 1
 Starter switch (Ignition switch-ST)
 ON
Other than IG-ST
 OFF
OK: Depending on the state of forced power supply output, the display is turned ON/OFF.

Q. Is the check result normal?
Go to Step 7
Replace the AS&G-ECU.

STEP 7. Check whether the diagnosis code is reset.

Q. Is the diagnosis code set?
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the OSS-ECU and register the chassis number (Refer to ).

STEP 8. M.U.T.-III data list
Check the OSS-ECU data list.
(1)Disconnect the engine-ECU connector.
(2)Using the M.U.T.-III, perform the forced power supply output.
State of forced power supply output
 Item No.
 Check item
 Display
IG-ST
 13
 Cranking signal output(monitor)
 ON
Other than IG-ST
 OFF
OK: Depending on the state of forced power supply output, the display is turned ON/OFF.

Q. Is the check result normal?
Replace the engine-ECU and register the chassis number and key codes [Refer to GROUP 00 - How to Perform Chassis Number (Chassis No.) Writing ].
Replace the OSS-ECU and register the chassis number (Refer to ).

STEP 9. Voltage measurement at ETACS-ECU connector (STOE terminal)
(1)Measure the ETACS-ECU connector side by backprobing.
(2)Using the M.U.T.-III, set the forced power supply output to other than "IG-ST".(Refer to .)
(3)Measure the voltage between the ETACS-ECU connector (STOE terminal) and body earth.
OK: 1 V or less
(4)Using the M.U.T.-III, set the forced power supply output to "IG-ST".(Refer to .)
(5)Measure the voltage between the ETACS-ECU connector (STOE terminal) and body earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 10
Replace the OSS-ECU and register the chassis number (Refer to ). Then go to Step 10

STEP 10. Check whether the diagnosis code is reset.

Q. Is the diagnosis code set?
Replace the ETACS-ECU.
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).