Inspection Procedure E-1: Keyless Entry System: Keyless Entry System Does Not Operate: Diagnosis

Required Special Tools: 

• MB991223: Test Harness Set
• MB991502: Scan Tool (MUT-II)

1. STEP 1. Check the central door locking system. 

   Q: Does the central door locking system work normally? 

   1. YES:  Go to Step 2.
   2. NO:  See INSPECTION PROCEDURE C-1: CENTRAL DOOR LOCKING SYSTEM: THE CENTRAL DOOR LOCK SYSTEM DOES NOT WORK AT ALL .
2. STEP 2. Check the input signal (by using the Pulse check). 

   Check input signals from the transmitter.

   CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
   1. Connect scan tool MB991502 to the data link connector.
   2. When the transmitter LOCK or UNLOCK switch is turned ON, check that scan tool MB991502 sounds.

   Q: When the transmitter LOCK or UNLOCK switch is turned ON, does scan tool MB991502 sound? 

   1. YES:  Replace the ETACS-ECU. All the doors can be locked or unlocked by means of the transmitter.
   2. NO:  See INSPECTION PROCEDURE R-10: TRANSMITTER: THE ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE LOCK, UNLOCK OR PANIC SWITCH .