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Inspection Procedure 10: ETACS-ECU does not receive any signal from the hood latch switch.
 
 
 
 
 
 
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 hood latch switch connector A-49 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is hood latch switch connector A-49 in good condition?
Go to Step 2.
Repair or replace the damaged component(s). Refer to GROUP 00E, Harness Connector Inspection . Check that the input signal of hood latch switch is normal.
 
STEP 2. Check the hood latch switch.
Remove the hood latch switch. Then check continuity between the switch terminals.
 
Switch positionTester connectionSpecified condition
Released1 - 2Less than 2 ohms
Pressed1 - 2Open circuit
Is the hood latch switch in good condition?
Go to Step 3.
Replace the hood latch switch. Check that the input signal of hood latch switch is normal.
 
STEP 3. Check the ground circuit to the hood latch switch. Test at hood latch switch connector A-49.
(1) Disconnect hood latch switch connector A-49 and measure the resistance available at the wiring harness side of the connector.
(2) Measure the resistance value between terminal 1 and ground.
  • The resistance should equal 2 ohms or less.
Is the measured resistance 2 ohms or less?
Go to Step 5.
Go to Step 4.
 
STEP 4. Check the wiring harness between hood latch switch connector A-49 (terminal 1) and ground.
Check the ground wires for open circuit.
Is the wiring harness between hood latch switch connector A-49 (terminal 1) and the ground in good condition?
No action is necessary and testing is complete.
The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Check that the input signal of hood latch switch is normal.
 
STEP 5. Check ETACS-ECU connector C-410 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Is ETACS-ECU connector C-410 in good condition?
Go to Step 6.
Repair or replace the damaged component(s). Refer to GROUP 00E, Harness Connector Inspection . Check that the input signal of hood latch switch is normal.
 
STEP 6. Check the wiring harness between driver's door switch connector A-49 (terminal 2) and ETACS-ECU connector C-410 (terminal 12).
Check the input lines for open circuit and short circuit.
Is the wiring harness between driver's door switch connector A-49 (terminal 2) and ETACS-ECU connector C-410 (terminal 12) in good condition?
Replace the ETACS-ECU. Check that the input signal of hood latch switch is normal.
The wiring harness may be damaged or the connector(s) may have loose, corroded or damaged terminals, or terminals pushed back in the connector. Repair the wiring harness as necessary. Check that the input signal of hood latch switch is normal.