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Inspection Procedure 15: The hood latch 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 hood latch switch input signal, the hood latch switch signal is no longer output to the communication line.
 
 
TROUBLESHOOTING HINTS
  • The hood latch 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 installation condition.
Check that the hood latch switch is installed to the body correctly.
Is the check result normal?
Go to Step 2.
Correct the installation condition.
 
STEP 2. hood latch switch check.
Refer to GROUP 42A - Hood .
Is the check result normal?
Go to Step 3.
Replace the hood latch switch.
 
STEP 3. Resistance measurement at hood latch switch connector (ground terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the resistance between the hood latch switch connector (ground terminal) and body ground.
OK: The resistance should be 2 ohms or less
Is the check result normal?
Go to Step 5.
Go to Step 4.
 
STEP 4. Check of open circuit in ground line between hood latch 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 5. Check of open circuit in HOOD line between hood latch switch connector and body ground.
Is the check result normal?
Go to Step 6.
Repair the connector(s) or wiring harness.
 
STEP 6. 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 hood latch switch.
  • Open the hood.
 
Item No.Item nameNormal conditions
90Hood switchON
Item No.Item nameNormal conditions
90Hood switchON
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.