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ECU speed wire cut

Airzone

By Airzone,
in General Maintenance

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Airzone Rising Star

Airzone

Posted
Posted

Hi,

It seems I found the problem with my HICAS... My car can do more than 180kph and that leads me to believe that the speed sensor wire has been cut. I managed to work out where the ECU is (thanks to the forum), and managed to work out how to remove the footwell (thanks to a mirror and torch).

I couldn't see any wire cut at the base of the ECU, nor any wires cut on the way into the wiring trunk.. This leads me to believe that it's cut elsewhere.

Will having this wire cut affect the car in any way (except for HICAS playing up and no speed limiter)? Just want to make sure it's worth the effort trying to get the dash off to look in the back of the speedo...

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https://www.sau.com.au/forums/topic/11928-ecu-speed-wire-cut/
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Guest RedLineGTR

Guest RedLineGTR

Posted
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there also is a wire directly near the hicas system with a speed wire, i couldnt tell you where but there is one on the ecu which is not the main one, which you may have problems if both are not cut, unless the main one near the hicas system which is the one that actaully measures the speed it will not work properly which is the case with yours.

Airzone Rising Star

Airzone

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Dr Drift - Here's the crux of that problem... I cannot for the life of me get the ECU out. I exposed it, took off the wiring cap (with much difficulty) but I could not get the ECU's bracket off the bolts it's mounted on. To describe further (stop me when I go wrong) there are 2 nuts and one screw that needs to be removed. The screw is down the bottom, and the nuts are up the top, and right up the back. I could move the top of the ECU's bracket off the bolt that it sits on, and the bottom of the ECU came free when I removed the screw that held it in, but I just can't get the back of the bracket off the bolt that it sits on.. It won't move foward, back, left or right. So tight...

Am I inviting trouble if I try to remove the ECU's cover while it's still bolted in place? I can then get in there with works digi-cam and get a couple of happy snaps.

Oh, and if I do somehow manage to remove the ECU bracket from the frame of the car, what's the best way of unplugging the wiring loom? Does the battery need to be disconnected, or just have the car off?

akeenan Grand Master

akeenan

Posted
Posted
My car can do more than 180kph and that leads me to believe that the speed sensor wire has been cut.

what speed have u taken ur car to? there are some differences between actual speed and what ur car shows on the speedo...for example ive taken my car past 180 on the speedo and it appears to cut out at approx 190km/h but in actual fact becuase of the calibration of things it is actually 180km/h....... if you've taken you car to eg: 230km/h fair enough but if eg: u've taken it to say 190. id say its just the difference in readings...

Airzone Rising Star

Airzone

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Nah, stock steering wheel. Something's a little weird 'cause Hicas will move my rear wheels while the car is stationary (not much more than a twitch though). No speed alert chime, and no speed limiter. Oh well, if it's not going to blow up my engine or anything, I'm not going to worry about it too much.

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