INSPECTION PROCEDURE E-3: Keyless Entry System: Encrypted code cannot be registered.: Diagnosis

Required Special Tools: 

• MB991223: Harness Set
• MB991958: Scan Tool (MUT-III Sub Assembly)
  • MB991824: Vehicle Communication Interface (V.C.I.)
  • MB991827: MUT-III USB Cable
  • MB991911: MUT-III Main Harness B

1. STEP 1. Verify trouble symptom. 

   Q: Can the encrypted code register mode be set? 

   YES  : Go to  Step 3.

   NO  : Go to  Step 2.

2. STEP 2. Check the input signal (by using the pulse check mode of the monitor). 

   Check the input signals from the following switches:

   • Key reminder switch
   • Hazard warning light switch
   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 to the data link connector.
   2. Operate scan tool MB991958 as follows:
      1. Select "SYSTEM SELECT."
      2. Select "SWS."
      3. Select "PULSE CHECK."
   3. Check scan tool MB991958 sounds or not.
   4. If the switches (see table below), which are applicable for the input signal check, are operated.
   INPUT SIGNAL CHECK
   
   

   ITEM NAME	CHECK CONDITION
   Key reminder switch	Remove and reinsert the ignition key
   Hazard warning light switch	Turn the from the hazard warning light switch "OFF" to "ON" position.

   Q: When the key reminder switch and the hazard warning light switch are operated, does scan tool MB991958 sound in each case? 

   Buzzer of scan tool MB991958 sounds normally : 

   Replace the ETACS-ECU. Verify that the encrypted code can be registered in the transmitter.

   Scan tool MB991958 does not sound when the ignition key is removed and reinserted  : Refer to INSPECTION PROCEDURE N-1 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE KEY REMINDER SWITCH  ."

   Scan tool MB991958 does not sound when the hazard warning light switch is turned from "OFF" to "ON"  : Refer to INSPECTION PROCEDURE N-2 "ETACS-ECU DOES NOT RECEIVE ANY SIGNAL FROM THE HAZARD WARNING LIGHT SWITCH  ."

   Fig 1: Connecting Scan Tool To Data Link Connector

   Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
3. STEP 3. Check the transmitter. 

   Q: When the transmitter's battery is replaced, can the encrypted code be registered? 

   YES  : No action is necessary and testing is complete.

   NO  : Replace the transmitter. If the encrypted code can not be registered by means of the new transmitter, replace the ETACS-ECU. Verify that the encrypted code can be registered in the transmitter.