Inspection Procedure 2
Inspection Procedure 2: The rear dome light does not illuminate normally.
TROUBLE JUDGMENT
The ETACS-ECU illuminates and extinguishes the rear dome light in accordance with the input signals below.
- Ignition switch (IG1)
- Key reminder switch
- Door switches
- Liftgate latch switch
- Front door lock actuator
TECHNICAL DESCRIPTION (COMMENT)
If this does not work normally, the above switch input circuit(s), rear dome light, or ETACS-ECU may have a problem.
PROBABLE CAUSES
- Malfunction of the key reminder switch
- Malfunction of door switch
- Malfunction of liftgate latch switch
- Malfunction of the front door lock actuator (RH)
- Malfunction of rear dome light
- Malfunction of the ETACS-ECU
- The wiring harness or connectors may have loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
- MB991958: Scan Tool (M.U.T.-III Sub Assembly)
- MB991824: Vehicle Communication Interface (V.C.I.)
- MB991827: M.U.T.-III USB Cable
- MB991910: M.U.T.-III Main Harness A (Vehicles with CAN communication system)
STEP 1. Front dome light operation check
Check that the front dome light illuminates and extinguishes normally.
Q. Does rear dome light work normally?
YES Go to Step 2.
NO Replace the ETACS-ECU.
STEP 2. Using scan tool MB991958, read the diagnostic trouble code.
(1)
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.
Connect scan tool MB991958. Refer to "How to connect scan too (M.U.T.-III) Reading and Clearing Diagnostic Trouble Codes."
(2)Turn the ignition switch to the "ON" position.
(3)Check whether the ETACS-ECU related DTC is set.
(4)Turn the ignition switch to the "LOCK" (OFF) position.
Q. Is the DTC set?
YES Diagnose the ETACS-ECU. Refer to Electronic Time and Alarm Control System (ETACS).
NO Go to Step 3.
STEP 3. Using scan tool MB991958, check data list.
Use the ETACS-ECU data list to check the signals related to the rear dome light.
- Turn the ignition switch to the "LOCK" (OFF) position.
- Remove the ignition key from the ignition key cylinder.
- Open each door.
- Open the liftgate.
Q. Does scan tool MB991958 display the items "Dr door unlock", "IG voltage", "Dr door ajar switch", "As door ajar switch", "RR door ajar switch", "RL door ajar switch", "Trunk/gate trunk ajar switch" and "Handle lock switch" as normal condition?
YES [Normal conditions are displayed for all items.] : Go to Step 4.
NO [Normal condition is not displayed for item No. 228.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 4 "ETACS-ECU does not receive any signal from the front door lock actuator" Inspection Procedure 4.
NO [Normal condition is not displayed for item No. 254.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 2 "ETACS-ECU does not receive any signal from the ignition switch (IG1)" Inspection Procedure 2.
NO [Normal condition is not displayed for item No. 256.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 5 "ETACS-ECU does not receive any signal from the front door switch (LH)" Inspection Procedure 5.
NO [Normal condition is not displayed for item No. 257.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 6 "ETACS-ECU does not receive any signal from the front door switch (RH)" Inspection Procedure 6.
NO [Normal condition is not displayed for item No. 258.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 7 "ETACS-ECU does not receive any signal from the rear door switch (LH)" Inspection Procedure 7.
NO [Normal condition is not displayed for item No. 259.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 8 "ETACS-ECU does not receive any signal from the rear door switch (RH)" Inspection Procedure 8.
NO [Normal condition is not displayed for item No. 260.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 9 "ETACS-ECU does not receive any signal from the liftgate switch" Inspection Procedure 9.
NO [Normal condition is not displayed for item No. 264.] : Troubleshoot the ETACS-ECU. Refer to Inspection Procedure 3 "ETACS-ECU does not receive any signal from the key reminder switch" Inspection Procedure 3.
STEP 4. Check rear dome light connector D-10 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q. Is rear dome light connector D-10 in good condition?
YES Go to Step 5.
NO Repair the damaged parts.
STEP 5. Rear dome light bulb check
Check that the rear dome light bulb is normal.
Q. Does rear dome light work normally?
YES Go to Step 6.
NO Replace the rear dome light bulb.
STEP 6. Check ETACS-ECU connector C-316 for loose, corroded or damaged terminals, or terminals pushed back in the connector.
Q. Is ETACS-ECU connectors C-316 in good condition?
YES Go to Step 7.
NO Repair the damaged parts.
STEP 7. Check the wiring harness between rear dome light D-10 connector terminal (No. 1/2) and ETACS-ECU connector C-316 (terminal No. 6/5)
Check the communication line for open or short circuit.
Q. Is wiring harness between rear dome light connector D-10 (terminal No. 1/2) and ETACS-ECU connector C-316 (terminal No. 6/5) in good condition?
YES Go to Step 8.
NO Repair the wiring harness.
STEP 8. Retest the system
Check that the rear dome light illuminates/extinguishes normally.
Q. Does rear dome light work normally?
YES The trouble can be an intermittent malfunction How to Cope With Intermittent Malfunctions).
NO Replace the ETACS-ECU.