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Hicas light and heavy steering.

GTROB

By GTROB,
in General Maintenance

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GTROB Collaborator

GTROB

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Hi All.

Currently have a problem with my Oz delivered R32 GTR. After you have been drinving for Approx 10 min the Hicas light comes on and then the steering will slowly get heavier until there is no power assist. If you then turn the car off and restart it, It will be ok for another 10 mins and it will do the same thing. I have Changed the power steering fluid I have also had the pump off (Fun job) and tested flow rates and pressures and all seemes to be ok. I have also completed all the self tests that are in the Nissan work shop manual and are unable to get any fault codes out of it. The strange part is it only started doing it after I installed a 320kmph Nismo speedo. Haven't had a chance to swap them back yet but that is next in line.

Any help or ideas would be great. (Not much fun when you can't steer them)

Cheers

Craig.

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Duncan Grand Master

Duncan

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Craig generally the HICAS error light comes on when the steering wheel is not on straight, did you remove the wheel when you did the dash? Try a search for "HICAS +light" you will find plenty of other threads about this

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Ant Collaborator

Ant

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You may have disturbed the vehicle speed sensor (VSS) wire to the HICAS controller - that is sourced from the dash in a R32.

The HICAS controller waits for a certain amount of time (and/or a certain set of conditions) for a VSS input, and then if none is detected the HICAS light comes on and the power steering (which the HICAS controller also controls) defaults to no/minimal assistance. Sounds like this is what you are seeing to me.

I thought that the controller throws a fault code saying that the VSS signal isn't present, but as you aren't moving in diagnostics mode then it may not as it has no way of knowing if the input is good or not.

Do a search for HICAS vehicle speed sensor, there have been a few threads just recently on this topic. The short version is test the VSS input to the HICAS controller, and if it isn't working, work your way back thru the wiring until you find the problem. If the VSS input is OK, then ignore everything I've said!

And in your case I'd definitely check the dash wiring, especially the VSS feed from the dash to the ECU, which I believe branches to the HICAS controller.

Also I believe that the HICAS controller has a tacho input as well (used for power steering control), not sure what happens if this is not present but as it is related to dash stuff that could also be a possible source of the problem.

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vas_95 Contributor

vas_95

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Hey

Another possible cause includes the battery voltage. If the voltage drops below a certain level the power steering shuts off and hence hicas light . Go to batteryworld they check the battery under load for free.

The battery should be beween 13-14 volts when running no accessories

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Oosh Veteran

Oosh

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Hey

Another possible cause includes the battery voltage. If the voltage drops below a certain level the power steering shuts off and hence hicas light . Go to batteryworld they check the battery under load for free.

The battery should be beween 13-14 volts when running no  accessories

Yeap, that happened in my GST-T, turned out to be dodgy wire between the alt and batt so it was recharging properly. Power steering used to shut off and some REALLY inconvenient times (mid-way through a corner).
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