HICAS Diagnostic

[Lozza150]

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).

[Lozza150]

What is HICAS? And do I have it?

Good question. HICAS is Nissan’s version of four wheel steering. It is an acronym for High Capacity Actively Controlled Suspension. Unlike other Japanese car manufacturers 4WS (eg Honda’s system) HICAS never exceeds +/- 1°. It is designed for high speed response rather than parking manoeuvres.

The system is electro-hydraulic - the ECU in the boot directs a hydraulic actuator at the rear axle to steer the rear wheels using the rearmost suspension links. The result is usually no more than 0.4° of movement. HICAS gives a touch of counter steer before settling with the rear wheel pointing the same way as the front. (Maybe this explains why my Skyline feels so loose on high-speed gravel...) This results in sharp turn-in, and enhanced stability at medium to high speeds.

[Lozza150]

What is SUPER HICAS

Nissan Skyline GT-R has the SUPER HICAS setup.

Aided by computer, Super HICAS enables a tightly-controlled power slide that cannot be implemented by any alternatives.

When attacking a corner, the rear wheels will steer in reverse first in order to sharpen the initial steering response. Then, when sensors sense that the car responds to steering, the rear wheels will steer in the same direction as the front wheels, thus immediately introduces rear-tyre slip which help adjusting the attacking angle. Since the computer is monitoring the whole process, the amount of oversteering is always under check. You need not to be afraid of losing control.

The Super HICAS system was also available on a few S13 models. As you can see htat would make drift that little bit easier.

[Yotis]

Does this HICAS diagnostics work for a 34 GTT as well?

[R32 GTS-t]

the hicas light on my car pretty much stays on all the time but occasionally turns off, i have an r32 i was wondering if the diagnostic procedure is the same .

[Greg]

What is the neutral sensor - i got this code?

[Greg]

HICAS Diagnostic Mode

There is a HICAS warning light in the instrument cluster. If it comes, on it is indicative of a problem.

R32: Check the HICAS oil level (power steering reservoir in some models, or a remote reservoir accessible from the boot)

R32 and R33: Check all HICAS electrical connections, and if the light remains on, follow the diagnostic below.

Note that having an aftermarket steering wheel fitted without the appropriate HICAS boss adaptor can also cause the HICAS system to show a fault.

1. Switch ignition off, transmission in neutral or auto in Park.
   
2. Start engine
   
3. Very quickly (with a couple of seconds), turn the steering wheel left and right about 20 degrees from centre five times, and then pump the brakes five times, then press the brake pedal once more this will enter diagnostic mode.
   
4. Drive forwards or backwards about 5 metres at a speed less than 10km/hr, this will enter full diagnostic mode.
   
5. The HICAS light in the instrument cluster will be flashing quickly (for normal) or will flash a code indicating any problems.
   
6. Long flash = first digit, short flash = second digit.
   
7. Diagnostics will return to normal after five minutes, or any speed over 10km/hr,
   or ignition is turned off.
   

HICAS Diagnostic Codes 1989-1993

1 HICAS solenoid right hand

2 HICAS solenoid left hand

3 Cut off valve

4 Power steering solenoid

5 Vehicle speed sensor

6 Steering angle sensor

7 Neutral position sensor

8 (Auto) Parking brake sensor, (Manual) Clutch sensor

9 (Auto) Inhibitor switch, (Manual) Neutral sensor

HICAS Diagnostic Codes 1993-1999

11 HICAS control unit

12 HICAS motor power supply not present

13 HICAS motor output not present

21 Vehicle speed sensor not present

22 Steering angle sensor not present

23 Steering angle sensor neutral or not present

24 Rear main sensor input not present

25 Rear sub sensor input not present

31 Parking brake sensor input not present

32 (Auto) Inhibitor switch input not present; (Manual) Neutral switch input not present

33 Engine speed signal not present

This information from "The Sky Is The Limit, A Book Of Skyline Stuff"

[lwells]

A couple of questions

1) What's the difference (beyond the obvious slight difference in how one enters the mode) between the methods posted by Lozza150 and Greg? Do both methods apply to all Skylines fitted with (Super) HICAS?

2) Using Lozza150's method , does HICAS go in to Mode B by default?

Cheers,

Lucien.

[williamsf1]

ok I am trying to self check this HICAS light fault.... now the question remains, does HICAS work, or is it marketing? votes for removal on the GTR? and did gibbo's race cars have it removed?

will have to run this check, as the light seems to come on on slight corners or hard accelleration....

ideas?

[lwells]

now the question remains, does HICAS work, or is it marketing? votes for removal on the GTR? and did gibbo's race cars have it removed?

Yes, it works insofar as it does turn the wheels. If that's a positive (it makes manevourability at very low speeds easier) or a negative (you never quite know what the car will do when you start to corner) if up to the driver.

The diagnostic mode should tell you exactly what's wrong.

LW.

[sav man]

I did the test, and it came up with 5 Vehicle speed sensor as the problem. Where is this sensor located?

[RichyR32GTR]

Another 2 cents.. I read somewhere that the hicas light will come on if an aftermarket steering wheel is installed and the steering wheel position sensor is not relocated correctly. If i drive in a straight line (open highway) for a couple of minutes without moving the wheel much , my light comes on and stays on till i turn off and restart the car. I know this is my problem as i have a momo steering wheel. Haven't got around to fixing the sensor yet though

[Silver'sR33]

I did the diagnostic and got codes 22 & 23, then as I went back into garage it started flashing quickly (the "good" sign), so I did the diagnostic again and got code 22. BTW I had no probs with the HICAS light before this just did the test out of curiosity.

Are:

22 Steering angle sensor not present

23 Steering angle sensor neutral or not present

big problems for the operation of HICAS?

[Lozza150]

If tyhe light does not come on, and the fuse is ok, id say everything is ok. does seem odd that the codes come up and the light stays off.

[Silver'sR33]

Hey actually maybe it was a wrong code, because I noted in another post somewhere I think that if you don't drive forward (or back) far enough you can get an erroneous code. I tried this test again twice going forward further and got the HICAS light flashing fast saying everything's ok. In any case unless it causes me any probs I'll leave it be.

On a side note - I've noticed people saying they disable HICAS because it develops problems and aussie mechanics never know how to deal with it, but as far as I know the 300zx had Super HICAS and that was delivered locally so Nissan mechanics at least would know how to fix it, and certainly there'd be others who've fixed 300s?

[R33S2]

The Super HICAS system was also available on a few S13 models. As you can see htat would make drift that little bit easier.

It is my understanding that hicas reduces the ability to DRIFT properly as what we are trying to do is loose grip on the tires and therefore DRIFT the rear end about whereas HICAS is trying to steer the tires in a direction that will give more grip according to what the EMS understands what the car is doing.

[Lozza150]

They say (they being the Engineers) SUPER HICAS provides a sharper turn in ... which might help flick the car out faster then help in the control of the steer.

Remember HICAS and SUPER HICAS only move the rear wheels up to a max of 1 degree

Hicas moves the rear wheels on GTST's 0.7 of a degree

[TimmyC]

OK i swear i read that HICAS doesn't even kick in till about 60km/h ??

is this true ?

also was hicas an option or what ?, what percentage of cars that came out of the factory were fitted with hicas do you guys rekon ?

my mates are always dissing my 32gtst cos its got hicas and apparantly it adds like an extra 100kgs is this right ?

[ScottKing GTS-4]

HICAS is at it's most active at high speeds as it is a high speed stability aid more then true 4WS. Can't see it weighing 100kgs. Most people don't even remove it, just "lock" it for drag duties usually.

OK i swear i read that HICAS doesn't even kick in till about 60km/h ??

is this true ?

also was hicas an option or what ?, what percentage of cars that came out of the factory were fitted with hicas do you guys rekon ?

my mates are always dissing my 32gtst cos its got hicas and apparantly it adds like an extra 100kgs is this right ?

[LastTemptation]

i hate hicas because i dont understand it..

recently my hicas light is coming on.. and doesnt go away. the only time i have seen my hicas light on is during ignition.. i havent experience hicas before.. when hicas kicks in is the light on the dash lit up? also how do i check that a previous owner hasnt disabled it with a lock kit? and if the hicas fluid needs to be topped up, where do i top it up with and with what? thanks