No. 3 Transmitter Id Code Cannot Be Reprogrammed [Keyless Entry System]

3	Transmitter ID code cannot be reprogrammed
DESCRIPTION	Malfunction in BCM circuit, keyless receive circuit.
POSSIBLE CAUSE	Keyless receiver malfunction Keyless receiver malfunction Keyless receiver power supply fuse malfunction Malfunction in wiring harness between keyless receiver and ground Malfunction in wiring harness between keyless receiver and BCM Malfunction in wiring harness between keyless receiver power supply fuses and keyless receiver BCM malfunction Malfunction in wiring harness between keyless receiver and BCM Malfunction BCM

DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	INSPECT POWER SUPPLY FUSE  Is the keyless receiver power supply fuse normal?	Yes	Go to the next step.
		No	Install an appropriate amperage fuse, then go to Step 6.
2	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: Power supply 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 6.
3	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 6.
4	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 6.
5	Measure the signal wave pattern for keyless receiver terminal D (6-pin) 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. (See BODY CONTROL MODULE (BCM) REMOVAL/INSTALLATION ).
		No	Replace the keyless receiver, then go to the next step. (See KEYLESS RECEIVER REMOVAL/INSTALLATION ).
6	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.