NO.2 ALL ON-BOARD DIAGNOSTIC 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 on-board diagnostic 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 switch system malfunction
―  BCM malfunction
―  Malfunction in wiring harness between BCM and door switch
•  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
•  Turn the ignition switch to the ON position.
•  Measure the voltage at the following BCM terminals:
―  IG1 signal (terminal 4I)
―  Power supply signal (terminal 1I, 1K, 4B)
•  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 16.
*4
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (SHORT TO POWER SUPPLY BETWEEN FUSE BLOCK AND BCM, OR BETWEEN BCM AND GROUND) OR ELSEWHERE
•  Turn the ignition switch to the LOCK position.
•  Disconnect the BCM connector.
•  Measure the voltage at the following BCM terminal (wiring harness-side):
―  IG1 signal (terminal 4I)
•  Is the voltage B+?
Yes
Repair the malfunctioning wiring harness, then go to Step 16.
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 3S/4G and ground?
Yes
Go to the next step.
No
Repair the wiring harness between the BCM and ground, then go to Step 16.
6
VERIFY IF MALFUNCTION CAUSE IS ERRATIC DOOR SWITCH SIGNAL
•  Measure the voltage at following BCM terminals.
―  Terminal 5AB (Front door switch (Driver-side))
―  Terminal 5V (Front door switch (Passenger-side))
―  Terminal 5Y (Rear door switch (LH))
―  Terminal 5Z (Rear door switch (RH))
―  Terminal 5T (Liftgate latch switch)
•  Is the terminal voltage normal?
Yes
Go to Step 11.
No
If terminal 5AB, 5V, 5Y, 5Z is not specified:
•  Go to the next step.
If terminal 5T is not specified:
•  Go to step 9.
7
INSPECT DOOR SWITCH
•  Inspect switches for all doors.
•  Are there operations normal?
Yes
Go to the next step.
No
Replace suspect door switch.
8
INSPECT BCM OR WIRING HARNESS (BETWEEN BCM AND DOOR LATCH SWITCHES FOR CONTINUITY)
•  Open all doors.
•  Is there continuity between BCM terminals 5V, 5Y, 5Z, 5AB and ground?
Yes
Repair the wiring harness between the BCM and door switches, then go to the next step.
No
Replace the BCM and reprogram the transmitter ID code, then go to the next step.
9
INSPECT LIFTGATE LATCH SWITCH
•  Inspect the liftgate latch switch.
•  Is the liftgate latch switch normal?
Yes
Go to the next step.
No
Replace liftgate latch switch.
10
INSPECT BCM OR WIRING HARNESS (BETWEEN BCM AND LIFTGATE LATCH SWITCH FOR OPEN OR SHORT)
•  Inspect for open or short circuit between BCM and liftgate latch switch.
•  Is the wiring harness and connectors normal?
Yes
Replace the BCM and reprogram the transmitter ID code, then go to the next step.
No
Repair the wiring harness between the BCM and liftgate latch switch, then go to the next step.
11
INSPECT POWER SUPPLY FUSE
•  Is the keyless receiver power supply fuse normal?
Yes
Go to the next step.
No
Install an appropriate amperage fuse.
12
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY BETWEEN FUSE BLOCK AND KEYLESS RECEIVER) OR ELSEWHERE
•  Turn the ignition switch to the ON position.
•  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 16.
13
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 16.
14
INSPECT IF MALFUNCTION IS IN WIRING HARNESS (NO CONTINUITY OR SHORT CIRCUIT BETWEEN THE KEYLESS RECEIVER AND THE BCM) OR ELSEWHERE
•  Turn the ignition switch to LOCK position.
•  Disconnect the keyless receiver (6-pin) and the BCM (24-pin) connector.
•  Inspect wiring harness and connectors for continuity between keyless receiver terminal D (6-pin) and BCM terminal 3E (24-pin).
•  Is the wiring harness and connectors normal?
Yes
Go to the next step.
No
Repair or replace suspect part, then go to Step 16.
15
INSPECT IF MALFUNCTION IS IN KEYLESS RECEIVER OR BCM
•  Measure the signal wave pattern for BCM terminal 3E 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.
16
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.