NO.2 ALL KEYLESS ENTRY SYSTEM FUNCTIONS INOPERATIVE [KEYLESS ENTRY SYSTEM]


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•  When performing an asterisked (*) troubleshooting inspection, slightly shake the wiring harness and connectors while performing the inspection to discover whether poor contact points are the cause of any intermittent malfunctions. If there is a problem, verify that the connectors, terminals and wiring harnesses are connected correctly and undamaged.

2
All keyless entry system functions inoperative
DESCRIPTION
•  Malfunction in BCM power supply circuit, door latch switch circuit, BCM ground circuit, or keyless receiver.
POSSIBLE CAUSE
•  Malfunction in IG1 or power supply signal circuit of BCM
―  BCM power supply fuse malfunction
―  Malfunction in wiring harness between BCM power supply fuses and BCM
•  Malfunction in door open/closed signal circuit of BCM
―  Door latch switch system malfunction
―  BCM malfunction
―  Malfunction in wiring harness between BCM and door latch switch
•  Malfunction in trunk lid/liftgate latch switch signal circuit
―  Open or short circuit in wiring between BCM and trunk lid/liftgate lid latch switch
―  Trunk lid/liftgate latch switch malfunction
•  Malfunction in BCM GND signal circuit
―  Malfunction in wiring harness between BCM and ground
•  Malfunction in keyless receiver
―  Keyless receiver malfunction
―  Malfunction in wiring harness between keyless receiver and BCM

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT BCM POWER SUPPLY FUSES
•  Are the BCM power supply fuses normal?
Yes
Go to the next step.
No
Install an appropriate amperage fuse.
2
INSPECT DOOR LATCH SWITCH INSTALLATION
•  Are the door latch switches installed securely?
Yes
Go to the next step.
No
Install the door latch switches securely, then go back to Step 5 of keyless entry system preliminary inspection.
*3
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN FUSE BLOCK AND BCM) OR ELSEWHERE
•  Switch the ignition to ON.
•  Measure the voltage at the following BCM terminals:
―  IG1 signal (terminal 4T)
―  Power supply signal (terminal 3J, 5B, 4S)
•  Is the voltage B+?
Yes
Go to the next step.
No
Repair the wiring harness between the fuse block and BCM, then go to Step 13.
*4
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FUSE BLOCK AND BCM, OR BETWEEN BCM AND GROUND) OR ELSEWHERE
•  Switch the ignition to off.
•  Disconnect the BCM connector.
•  Measure the voltage at the following BCM terminal (wiring harness-side):
―  IG1 signal (terminal 4T)
•  Is the voltage B+?
Yes
Repair the malfunctioning wiring harness, then go to Step 13.
No
Go to the next step.
*5
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN BCM AND GROUND) OR ELSEWHERE
•  Is there continuity between BCM terminal 2N, 4B and ground?
Yes
Go to the next step.
No
Repair the wiring harness between the BCM and ground, then go to Step 13.
6
INSPECT IF MALFUNCTION IS IN DOOR, TRUNK LID/ LIFTGATE LATCH SWITCH SIGNALS OR ELSEWHERE
•  Monitor following BCM (door, trunk lid/liftgate latch switch) PID using the M-MDS.
―  TR/LG_SW (Trunk lid/liftgate latch switch)
―  DRSW_P (Passenger’s door latch switch)
―  DRSW_D (Driver’s door latch switch)
―  DRSW_LR (Rear door latch switch (LH))
―  DRSW_RR (Rear door latch switch (RH))
•  Are monitored PID values normal?
Yes
Go to Step 7.
No
Go to the next step.
7
INSPECT BCM OR WIRING HARNESS (BETWEEN BCM AND DOOR LATCH SWITCHES FOR CONTINUITY)
•  Open and close all doors.
•  Verify continuity between BCM terminals 6G, 6H, 6K, 6E, 6F and ground.
•  Are there continuities followings?
Door latch switches (Terminal 6G, 6H, 6K, 6E):
―  Open: Not continuity
―  Close: Continuity
Trunk lid/liftgate latch switches (Terminal 6F):
―  Open: Continuity
―  Close: Not continuity
Yes
Replace the BCM and reprogram the transmitter ID code, then go to the next step.
No
•  Inspect for open or short circuit in wiring harness between BCM and suspected door latch/trunk lid/liftgate latch switch.
―  If wiring harness is normal, inspect suspect door latch/trunk lid/liftgate latch switch.
―  If wiring harness malfunction, repair or replace wiring harness, then go to Step13.
8
INSPECT POWER SUPPLY FUSE
•  Is the keyless receiver power supply fuse normal?
Yes
Go to the next step.
No
Inspect and repair short to GND in wiring harness at keyless receiver power supply circuit install an appropriate amperage fuse, then go to step 13.
9
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN FUSE BLOCK AND KEYLESS RECEIVER) OR ELSEWHERE
•  Measure the voltage at the following keyless receiver terminal:
―  B+ signal (terminal A)
•  Is the voltage B+?
Yes
Go to the next step.
No
Repair the wiring harness between the fuse block and keyless receiver, then go to Step 13.
10
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN KEYLESS RECEIVER AND GROUND) OR ELSEWHERE
•  Is there continuity between keyless receiver terminal E and ground?
Yes
Go to the next step.
No
Repair the wiring harness between the keyless receiver and ground, then go to Step 13.
11
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN KEYLESS RECEIVER AND BCM) OR ELSEWHERE
•  Disconnect the keyless receiver connector and BCM connector.
•  Is there continuity between the following terminals?
―  4K (BCM connector)—D (keyless receiver connector)
Yes
Go to the next step.
No
Repair the wiring harness between the keyless receiver and BCM, then go to Step 13.
12
INSPECT IF MALFUNCTION IS IN KEYLESS RECEIVER OR BCM
•  Measure the signal wave pattern for BCM terminal 4K using an oscilloscope when the transmitter is operated with the key not inserted into the ignition key cylinder.
•  Does the wave pattern change when the transmitter is operated?
Note
•  Perform the oscilloscope setting using 0.5V/DIV (Y), 100ms/DIV (X), DC range.
Yes
Replace the BCM, then go to the next step.
No
Replace the keyless receiver, then go to the next step.
13
REINSPECT MALFUNCTION SYMPTOM AFTER REPAIR
•  Does the keyless entry system operate properly?
Yes
Troubleshooting completed.
Explain repairs to the customer.
No
Reinspect the malfunction symptoms, then repeat from Step 1 if the malfunction recurs.