[Previous][Next]
Inspection Procedure 2: Vehicle power does not turn ON. (not possible with both of power supply mode ACC and ON)
 
 
cautionBefore replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
 
 
 
 
TECHNICAL DESCRIPTION (COMMENT)
When the vehicle power does not turn ON (not possible with both of power supply mode ACC and ON), the battery, CAN bus line, OSS-ECU, OSS-ECU power supply, or ground circuit may have a problem.
noteOSS-ECU can communicate with the scan tool (M.U.T.-III) even when the engine switch is in the "OFF" position.
 
 
TROUBLESHOOTING HINTS
  • Malfunction of battery
  • Damaged wiring harness and connectors
  • Malfunction of engine switch (poor connector contact, poor engine switch contact)
  • Malfunction of the CAN bus line
  • Malfunction of ETACS-ECU
  • Malfunction of OSS-ECU
 
 
DIAGNOSIS
STEP 1. Battery check
Perform the battery test to check the battery status. (Refer to GROUP 54A - Battery .)
Is the check result normal?
Go to Step 2.
Replace the battery.
 
STEP 2. Using scan tool (M.U.T.-III), communicates with this system.
Check that the communication with scan tool (M.U.T.-III) is possible.
noteIf ETACS-ECU is not active, OSS-ECU cannot communicate with the scan tool (M.U.T.-III).
(1)
cautionTo prevent damage to scan tool (M.U.T-III), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (M.U.T-III).
Connect scan tool (M.U.T-III). Refer to "How to connect scan tool (M.U.T.-III) ."
(2) Turn the power supply mode of the engine switch to ON.
(3) Open the driver’s side door.
(4) Check that OSS-ECU can communicate with the scan tool (M.U.T.-III).
(5) Turn the power supply mode of the engine switch to OFF.
Is the check result normal?
Go to Step 3.
Carry out the troubleshooting of "OSS-ECU power supply or ground circuit malfunction".(Refer to .)
 
STEP 3. Using scan tool (M.U.T-III), diagnose the CAN bus line.
(1)
cautionTo prevent damage to scan tool (M.U.T-III), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (M.U.T-III).
Connect scan tool (M.U.T-III). Refer to "How to connect scan tool (M.U.T.-III) ."
(2) Turn the power supply mode of the engine switch to ON.
(3) Diagnose the CAN bus line.
(4) Turn the power supply mode of the engine switch to OFF.
Is the CAN bus line found to be normal?
Go to Step 4.
Repair the CAN bus line (Refer to GROUP 54C, Diagnosis ).
 
STEP 4. Using scan tool (M.U.T.-III), read the diagnostic trouble code.
Check if the diagnosis trouble code is stored in the OSS-ECU.
(1)
cautionTo prevent damage to scan tool (M.U.T.-III), always turn the power supply mode of the engine switch to the OFF position before connecting or disconnecting scan tool (M.U.T.-III).
Connect scan tool (M.U.T.-III). Refer to "How to connect scan tool (M.U.T.-III) ."
(2) Turn the power supply mode of the engine switch to ON.
(3) Check if DTC is stored.
(4) Turn the power supply mode of the engine switch to OFF.
Is the DTC stored?
Refer to diagnostic trouble code chart .
Go to Step 5.
 
STEP 5. Engine switch check
Continuity check of engine switch.
 
Switch operationTerminal numberNormal value
Press6 - 2Continuity exists (2 Ω or less)
10 - 4
Release6 - 2No continuity
10 - 4
Is the check result normal?
Go to Step 6.
Replace the engine switch.
 
STEP 6. Check of the troubles
Check that the vehicle power can be turned ON.
Is the check result normal?
Intermittent malfunction is suspected (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction ).
Carry out the troubleshooting relevant to the input signal of ETACS-ECU (Refer to GROUP 54A - ETACS ). Then, go to Step 7.
 
STEP 7. Check of the troubles
Check that the vehicle power can be turned ON.
Is the check result normal?
This diagnosis is complete.
Replace the OSS-ECU and register the VIN (Refer to ).