[Previous][Next]
Inspection Procedure 16: The LDW switch signal is not received.
 
 
caution
  • Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
 
 
TECHNICAL DESCRIPTION (COMMENT)
If there is an error to the LDW switch input signal, the LDW switch signal is no longer output to the communication line.
 
 
TROUBLESHOOTING HINTS
  • The LDW switch may be defective
  • The ETACS-ECU may be defective
  • The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Check the LDW switch.
Check the LDW switch. Refer to .
Is the check result normal?
Go to Step 2.
Replace the LDW switch.
 
STEP 2. Resistance measurement at LDW switch connector (ground terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the resistance between the LDW switch connector (ground terminal) and body ground.
OK: The resistance should be 2 ohms or less
Is the check result normal?
Go to Step 4.
Go to Step 3.
 
STEP 3. Check of open circuit in ground line between LDW switch connector and body ground.
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 ).
Repair the connector(s) or wiring harness.
 
STEP 4. Check of short to ground, and open circuit in LDWS line between LDW switch connector and ETACS-ECU connector.
Is the check result normal?
Go to Step 5.
Repair the connector(s) or wiring harness.
 
STEP 5. Using scan tool (M.U.T.-IIISE), check data list.
Check the ETACS-ECU data list.
(1)
cautionTo prevent damage to scan tool (M.U.T.-IIISE), always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool (M.U.T.-IIISE).
Connect scan tool (M.U.T.-IIISE). Refer to "How to connect Scan Tool (M.U.T.-IIISE) ."
(2) Check the input signals from the LDW switch.
  • LDW switch is pressed.
 
Item No.Item nameNormal condition
109LDW switchON
  • LDW switch is not pressed.
 
Item No.Item nameNormal condition
109LDW switchOFF
OK: Normal condition is displayed.
Is the check result normal?
The trouble can be an intermittent malfunction (Refer to GROUP 00 - How to use Troubleshooting/inspection Service Points - How to Cope with Intermittent Malfunction ).
Replace the ETACS-ECU.