240sx HICAS diagnostic procedure

HICAS Diagnostic Procedure

1. Input starting conditions for self-diagnosis.
* Turn ignition switch “OFF”.
* Set shift lever to “P” or “N” (A/T) or “Neutral” (M/T).
* Turn ignition switch “ON”.
* Immediately start engine.
* Turn steering wheel from left to right (at least 20deg from the neutral position) 5- times or more, then depress foot brake pedal at least 5- times all within 10- seconds after ignition switch has been turned “ON”.

2. Input self-diagnosis item.
* Depress and release foot brake pedal.
* Turn steering wheel from left to right (at least 20deg) from the neutral position.

* (M/T model):
Depress clutch pedal and move gear shift lever to any position other than Neutral and return to Neutral. Release clutch pedal.

(A/T model):
Disengage and engage parking brake lever. Move shift lever to any position other than Neutral or Parking and return to Parking.
* Move car at least 3 meters (10ft) forward and proceed at indicated speed of at least 2km/h (1mph) in self-diagnosis mode.

3. The self-diagnosis mode will then appear in the “HICAS” warning lamp.
* When all systems are normal HICAS warning lamp flashes at 0.25 second intervals.
* When there is a system malfunction (there is a nifty diagram here of HICAS lamp pulses. I tried to translate them to words…)

Mode A)
10 short pulses for 5 seconds.
No pulses for 5 seconds.
Nine 2-second interval indicating the system status (18 seconds total).
(short pulse = good, 1 second pulse=bad)
1) HICAS Solenoid R.H.
2) HICAS Solenoid L.H.
3) Fail-Safe Valve
4) (Constantly normal mode)
5) Vehicle Speed Sensor
6) Steering Angle Sensor
7) Steering Neutral Position Sensor
8) A/T: Parking brake sensor
M/T: Clutch Sensor
9) A/T: Inhibitor Sensor
M/T: Neutral Sensor

** Display repeats until ignition switch is turned “OFF” or 5 min has past.

Mode B)
Lamp on for 5 seconds.
No pulses for 5 seconds.
Nine 2-second interval indicating the system status (18 seconds total).
(short (0.1 sec) pulse = good, 1 second pulse=bad)
1) HICAS Solenoid R.H.
2) HICAS Solenoid L.H.
3) Fail-Safe Valve
4) (Constantly normal mode)
5) Vehicle Speed Sensor
6) Steering Angle Sensor
7) Steering Neutral Position Sensor
8) A/T: Parking brake sensor
M/T: Clutch Sensor
9) A/T: Inhibitor Sensor
M/T: Neutral Sensor

** Display repeats until ignition switch is turned “OFF” or 5 min has past.

Note 1: To change the display mode to “A”, turn OFF ignition switch after mode “B” is displayed. When battery is insufficient, mode “B” is displayed.

Note 2: If fail-safe system was operated (fail-safe valve is operating) when ignition switch was turned OFF for the last time, mode A will be displayed. If fail-safe system was not operated when the ignition switch was turned OFF for the last time, mode B will be displayed.

* Canceling the self-diagnosis function

Three methods.
1) By turning the ignition switch off.
2) After self-diagnosis has been operated for ~5 minutes.
3) If the vehicle speed goes over 30 km/h (19 mph).