R33 Power Steering plz help

[bnsportsr33]

Hi, It seems I have lost all power steering in my R33, I did notice it was a little bit low in the resevoir so I filled it up, and also I do notice it's a little wet at the bottom of the resevoir where the line is connected

my question is, is there a way to test ps pump while it is still on the car? or a way to diagnose what my issue may be, I imagine it could only be a few things: lines, pump, rack? anything else, other ideas? thanks

[Skym]

Common for the stock power steering hose clamps to be not good enough (replace them with small worm drive clamps).

HICAS ECU controls a valve on front rack that controls power steering assistance. If HICAS ECU detect's fault (bad sensor, bad alternator, etc) it goes into a limp mode, where it provides front rack the same assistance as it would at around 175-200km/h, which makes the steering feel heavy at lower speeds.

Also there is a procedure you follow in manual that shows how to find the HICAS ECU error codes (I think flashes HICAS light on dash, sort of like morse code and you match to list of how many blinks, etc = name of sensor, etc).

[bnsportsr33]

hmm how do i get it our of limp mode? if in fact that is the case, which manual are we talking? the workshop manual? if so do you know roughly where it would be in the manual, thanks

[Skym]

Should be in the workshop manual. Not sure on page. Need to find out what is the cause, could be HICAS ECU itself or sensor (steering angle sensor behind steering wheel due to incorrect aftermarket boss kit or failed steering angle sensor, faulty speedo cable, etc).

It's fairly easy to get into HICAS diagnostic mode. Turn engine on and quickly turn steering wheel left to right and right to left I think was 5 times and press brake pedal. If drive backwards or forwards at less than I think was 30km/h? it puts HICAS ECU into full diagnostic mode. It should then flash the error codes on dash via HICAS light and should repeat that error code (just like morse code). If drive over 30km/h or turn engine off then HICAS ECU should exit this diagnostic mode.

When I did the above, rear HICAS rack started to move around (HICAS ECU was damaged). It's common for HICAS ECU to have bad solders inside and sometimes water enters breather holes on top of HICAS ECU (what happened on my car when steering went heavy) if rear window is leaking or trunk lid isn't tightened down properly.

Solution on my car was to swap HICAS ECU out with same HICAS ECU from another car (be aware that HICAS ECU part numbers are different between GTS, GTR), turn it upside down (so breather holes face downwards) which fixed the heavy steering problem.

[bnsportsr33]

hmmm lol ok, i guess i'm going to have to put another bulb in my hicas light then cuz it was permanently on and i removed it... I have GT-R cluster too, is that going to make a difference? I honestly think it might be the ps pump anyways, i was wondering if there was a way to test it

thnx for the info tho bud appreciate it

[bnsportsr33]

oh that's right I have a HICAS delete bar, does that make any difference?

[SlidingSideways]

Lol @ skym

[bnsportsr33]

why lol @ skym?

[Skym]

The rear of car getting jiggy with it.

The GTR cluster could affect the assistance amount (might be calibrated differently, check on speedo testing dyno at a speedo specialist) as is speed related.

Did you electronically disable the HICAS ECU when fitting lockbar??? Tomei sell a kit that electronically, mechanically disables HICAS.

[bnsportsr33]

Car came with HICAS delete bar, I have no idea if they electronically disabled the HICAS ECU... car was a drift car in Japan

[bnsportsr33]

so i'm assuming that whole theory about the HICAS is out of the question if I have a delete bar , am i correct? i just wanna figure this out so I can reg the car and bring it out, mind you it's pretty shitty here still but ya

[Skym]

The HICAS ECU controls the powersteering assistance. There's probably a plug that was unplugged, part that was removed, but not earthed the plug to tell ECU that part is still there, but it isn't (what the electronic part of Tomei HICAS lock kit does).