NATS (Nissan Anti-Theft System) / Gasoline engine — Trouble Diagnoses (Cont'd) — Diagnostic Procedure 7 (SECURITY IND. DOES NOT LIGHT UP) (Supplement-VII)
EL-7072flowchartProcedure 7: Security indicator dead. Tests fuse 24 → wire voltage → bulb → IMMU pulse output (pin 6). Intermittent continuity at pin 6 = expected blink pattern.
Trouble Diagnoses (Cont'd)
DIAGNOSTIC PROCEDURE 7
'SECURITY IND. DOES NOT LIGHT UP'
Procedure 7 — Security indicator non-functional
1
Check 10A fuse [No 24], located in the fuse block (J/B).
NG
Replace fuse.
OK
2
NATS INITIALIZATION. 1) Install the 10A fuse. 2) Perform initialization with CONSULT-II. For the operation of initialization, refer to 'CONSULT-II operation manual NATS'.
3
Turn ignition switch 'OFF'.
4
Start engine and turn ignition switch 'OFF'.
5
Check the security ind. lighting.
OK
END
NG
6
[A] Check voltage between security ind. connector terminal 1 and ground. Voltage: Battery voltage.
NG
Check harness for open or short between fuse and security ind.
OK
7
CHECK INDICATOR LAMP.
NG
Repair harness.
OK
8
[B] CHECK NATS IMMU FUNCTION. 1) Connect NATS IMMU connector. 2) Disconnect security ind. connector. 3) Check continuity between NATS IMMU terminal 6 and ground. Continuity should exist intermittently.
NG
NATS IMMU is malfunctioning. Replace IMMU. + Perform initialization with CONSULT-II.
OK
9
Check harness for open or short between security indicator and NATS IMMU.
NOTE
Diagnostic for the case where the security indicator (anti-theft LED) doesn't blink at all. Procedure tests:
1. 10A fuse [No 24] — replace if blown, then re-init
2. Indicator wire voltage at connector pin 1 — should be battery voltage
3. Indicator bulb itself — replace if burned out
4. IMMU output pin 6 — should pulse to ground intermittently (this is what makes the LED blink). If no pulse, IMMU is bad.
WARNING
Indicator-not-blinking ≠ NATS not working. NATS may still function (engine starts normally) — but if customer needs the anti-theft 'visible deterrent', this is the procedure to use.