Code No.B1133 IG1 setting circuit fail


caution 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 IG1 signal is ON, the IG1 circuit voltage is less than 1.5 V.
  2. When the IG1 signal is OFF, the IG1 circuit voltage is 3.5 V or more.

PROBABLE CAUSES



  • Damaged wiring harness or connector (short to earth or short to power supply in IG1 line)
  • Malfunction of OSS-ECU
  • ETACS-ECU malfunction

DIAGNOSIS PROCEDURE

STEP 1. Check of short to power supply, short to earth, and open circuit in IG1 line between OSS-ECU connector and ETACS-ECU connector
note Before the wiring harness check, check the joint connector, and repair if necessary.

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

STEP 2. Voltage measurement at ETACS-ECU connector (IG1 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-ON".(Refer to .)
(3)Measure the voltage between the ETACS-ECU connector (IG1 terminal) and body earth.
OK: 1 V or less
(4)Using the M.U.T.-III, set the forced power supply output to "IG-ON".(Refer to .)
(5)Measure the voltage between the ETACS-ECU connector (IG1 terminal) and body earth.
OK: System voltage

Q. Is the check result normal?
Go to Step 3.
Replace the OSS-ECU and register the chassis number (Refer to ).

STEP 3. M.U.T.-III data list
Check the OSS-ECU data list.
Power supply mode
 Item No.
 Check item
 Display
ON
 15
 IG1 output (monitor)
 ON
Other than ON
 OFF
OK: Depending on the state of power supply mode, the display is turned ON/OFF.

Q. Is the check result normal?
Go to Step 4.
Replace the OSS-ECU and register the chassis number (Refer to ).

STEP 4. 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 )