NO.2 ALL KEYLESS ENTRY SYSTEM FUNCTIONS INOPERATIVE [KEYLESS ENTRY SYSTEM]
id0903d2898600
2
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All keyless entry system functions inoperative
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DESCRIPTION
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• Malfunction in BCM power supply circuit, door latch switch circuit, BCM ground circuit, or keyless receiver.
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POSSIBLE CAUSE
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• Malfunction in IG1 or power supply signal circuit of BCM
• Malfunction in door open/closed signal circuit of BCM
• Malfunction in trunk lid/liftgate latch switch signal circuit
• Malfunction in BCM GND signal circuit
• Malfunction in keyless receiver
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Diagnostic procedure
STEP |
INSPECTION |
ACTION |
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1
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INSPECT BCM POWER SUPPLY FUSES
• Are the BCM power supply fuses normal?
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Yes
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Go to the next step.
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No
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Install an appropriate amperage fuse.
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2
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INSPECT DOOR LATCH SWITCH INSTALLATION
• Are the door latch switches installed securely?
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Yes
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Go to the next step.
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No
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Install the door latch switches securely, then go back to Step 5 of keyless entry system preliminary inspection.
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*3
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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:
• Is the voltage B+?
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Yes
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Go to the next step.
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No
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Repair the wiring harness between the fuse block and BCM, then go to Step 13.
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*4
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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):
• Is the voltage B+?
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Yes
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Repair the malfunctioning wiring harness, then go to Step 13.
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No
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Go to the next step.
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*5
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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?
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Yes
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Go to the next step.
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No
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Repair the wiring harness between the BCM and ground, then go to Step 13.
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6
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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.
• Are monitored PID values normal?
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Yes
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Go to Step 7.
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No
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Go to the next step.
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7
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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):
Trunk lid/liftgate latch switches (Terminal 6F):
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Yes
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Replace the BCM and reprogram the transmitter ID code, then go to the next step.
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No
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• Inspect for open or short circuit in wiring harness between BCM and suspected door latch/trunk lid/liftgate latch switch.
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8
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INSPECT POWER SUPPLY FUSE
• Is the keyless receiver power supply fuse normal?
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Yes
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Go to the next step.
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No
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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.
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9
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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:
• Is the voltage B+?
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Yes
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Go to the next step.
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No
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Repair the wiring harness between the fuse block and keyless receiver, then go to Step 13.
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10
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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?
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Yes
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Go to the next step.
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No
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Repair the wiring harness between the keyless receiver and ground, then go to Step 13.
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11
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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?
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Yes
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Go to the next step.
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No
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Repair the wiring harness between the keyless receiver and BCM, then go to Step 13.
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12
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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?
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Yes
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Replace the BCM, then go to the next step.
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No
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Replace the keyless receiver, then go to the next step.
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13
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REINSPECT MALFUNCTION SYMPTOM AFTER REPAIR
• Does the keyless entry system operate properly?
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Yes
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Troubleshooting completed.
Explain repairs to the customer.
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No
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Reinspect the malfunction symptoms, then repeat from Step 1 if the malfunction recurs.
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