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Inspection Procedure B-6: Half latch switch and/or full latch switch signals are not received.
 
 
cautionBefore replacing the ECU, ensure that the input and output signal circuits are normal.
 
 
 
 
COMMENTS ON TROUBLE SYMPTOM
There may be a malfunction in one of the followings; the wiring harness or its connector(s) between the power liftgate control unit and the half latch switch, the wiring harness or its connector(s) between the power liftgate control unit and the full latch switch, the liftgate latch switch itself or the power liftgate control unit itself.
 
 
PROBABLE CAUSES
  • Damaged liftgate latch
  • Damaged power liftgate control unit
  • Damaged wiring harness and connectors
 
 
DIAGNOSIS
Required Special Tools:
  • MB991223: Harness Set
  • MB992006: Extra Fine Probe
STEP 1. Using scan tool (M.U.T.-IIISE), check data list
(1) Disconnect the negative battery terminal and wait for approximately 30 seconds.
(2) Check the signals related to the power liftgate operation.
  • Half latch switch: OFF → ON
  • Full latch switch: OFF → ON
 
Item No.Item nameNormal conditions
5Half latch switchOFF → ON
6Full latch switchOFF → ON
OK: Normal conditions are displayed for all the items.
Is the check result normal?
: Go to Step 9.
: Go to Step 2.
: Go to Step 5.
: Go to Step 7.
 
STEP 2. Half-latch and full-latch switches check
Check the liftgate latch (refer to ).
Is the check result normal?
Go to Step 3.
Replace the liftgate latch.
 
STEP 3. Resistance measurement at liftgate latch connector (half-latch switch/full latch switch ground line terminal).
(1) Disconnect the connector, and measure at the wiring harness side.
(2) Measure the resistance between liftgate latch connector (half-latch switch/full latch switch ground line terminal) and body ground.
OK: Continuity exists (2 Ω or less).
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Go to Step 4.
 
STEP 4. Check of open circuit in ground line between liftgate latch connector (half-latch switch/full latch switch terminal) and body ground.
Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.
 
STEP 5. Half-latch switch check
Check the liftgate latch (refer to ).
Is the check result normal?
Go to Step 6.
Replace the liftgate latch.
 
STEP 6. Check of open circuit in HARF line between power liftgate control unit connector and liftgate latch connector.
Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.
 
STEP 7. Full-latch switch check
Check the liftgate latch (refer to ).
Is the check result normal?
Go to Step 8.
Replace the liftgate latch.
 
STEP 8. Check of open circuit in FULL line between power liftgate control unit connector and liftgate latch connector.
Is the check result normal?
Go to Step 9.
Repair the connector(s) or wiring harness.
 
STEP 9. Check of the troubles
Check whether the half latch switch and/or the full latch switch signal are received normally.
Is the check result normal?
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)
Go to Step 10.
 
STEP 10. After the replacement of liftgate latch, recheck the trouble symptom.
(1) Replace the liftgate latch.
(2) Check whether the half latch switch and/or the full latch switch signal are received normally.
Is the check result normal?
The procedure is complete.
Replace the power liftgate control unit.