Inspection Procedure 17
Inspection Procedure 17: The Trunk Is Not Opened When The Keyless Operation Key "TRUNK" Button Is Operated.CAUTION: Before replacing the ECU, ensure that the power supply circuit, the ground circuit and the communication circuit are normal.
Keyless Operation Key "TRUNK" Input Signal (Part 1):
Keyless Operation Key "TRUNK" Input Signal (Part 2):
TECHNICAL DESCRIPTION (COMMENT)
The receiver antenna assembly receives the trunk signals from the keyless operation key, and sends them to KOS-ECU, and further to ETACS-ECU. Then the ETACS-ECU determines to actuate the trunk open function of the keyless entry system.
TROUBLESHOOTING HINTS
- The keyless operation key may be defective
- The receiver antenna assembly may be defective
- The KOS-ECU 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:
- MB992006: Extra fine probe
- MB991223: Harness set
- MB991958 Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicles Communication Interface (V.C.I.)
- MB991827 M.U.T.-III USB Cable
- MB991910 M.U.T.-III Main Harness A
STEP 1. Check the operation of the keyless operation system (keyless entry system).
Operate the keyless operation key and check that all doors lock and unlock.
Q: Is the check result normal?
YES : Go to Step 2.
NO : Refer to inspection procedure 14: "Keyless entry system does not work." Inspection Procedure 14
STEP 2. Using scan tool MB991958, read the diagnostic trouble code.
CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
1. Connect scan tool MB991958. Refer to "How to connect scan tool (M.U.T.-III)." How To Connect The Scan Tool (M.U.T.-III)
2. Turn the ignition switch to the "ON" position.
3. Check whether the KOS-ECU related DTC is set.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the KOS-ECU. Diagnostic Trouble Code Descriptions
NO : Go to Step 3.
STEP 3. Check trunk lid latch connector F-19 and ETACS-ECU connector C-311 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q: Is trunk lid latch connector F-19 and ETACS-ECU connector C-311 in good condition?
YES : Go to Step 4.
NO : Repair or replace the damaged component(s).
STEP 4. Check the trunk lid latch assembly.
Remove the trunk lid latch assembly.
Q: Is the trunk lid actuator normal?
YES : Go to Step 5.
NO : Replace the trunk lid latch assembly.
STEP 5. Check the ground circuit to the trunk lid lock actuator. Measure the resistance at trunk lid lock actuator connector F-19.
1. Disconnect trunk lid lock actuator connector F-19 and measure the resistance available at the wiring harness side of the connector.
2. Measure the resistance value between terminal 2 and ground.
- The resistance should be 2 ohms or less.
Q: Is the measured resistance 2 ohms or less?
YES : Go to Step 7.
NO : Go to Step 6.
STEP 6. Check the wiring harness between trunk lid latch connector F-19 (terminal 2) and ground.
- Check the ground wires for open circuit.
NOTE: Also check intermediate connector F-27 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connector F-27 is damaged, repair or replace the damaged component(s).
Q: Is the wiring harness between trunk lid latch connector F-19 (terminal 2) and ground in good condition?
YES : No action is necessary and testing is complete.
NO : 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 trunk lid opener function works normally.
STEP 7. Check the wiring harness between trunk lid latch connector F-19 (terminal 3) and ETACS-ECU connector C-311 (terminal 1).
- Check the input/output line for open or short circuit.
NOTE: Also check intermediate connectors D-17, F-27 for loose, corroded, or damaged terminals, or terminals pushed back in the connector. If intermediate connectors D-17, F-27 is damaged, repair or replace the damaged component(s).
Q: Is the wiring harness between trunk lid latch connector F-19 (terminal 3) and ETACS-ECU connector C-311 (terminal 1) in good condition?
YES : Go to Step 8.
NO : 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 trunk lid opener function works normally.
STEP 8. Check of the troubles
Operate the keyless operation key and check that the trunk lid can be opened.
Q: Is the check result normal?
YES : The diagnosis is complete.
NO : Replace the ETACS-ECU. When the ETACS-ECU is replaced, register the keyless ID. The trunk lid can be opened by means of the keyless operation key.