I am getting a code 14 and intermittent loss of power steering. I understand code 14 is speed sensor, my speedometer is working fine even when the power steering fails, could they be related? First thing I will do is clean the connectors on the speed sensor, what else can I do to diagnose?

 

Thanks, Dan

Not, not now. :)

I had pretty much the same thing on my uk spec.

Once the clocks were eliminated it was traced back to the hicas ecu.

Replaced that as resoldering didnt help. All been fine ever since.

I've replaced or fixed pretty much every ecu on this car now. Started falling like dominoes.

 

- - - Updated - - -

 

It passes through hicas first from what i recall.

Could be faulty speed sensor on the gearbox..... Has a manual conversion been done because the auto and manual are different

Surely the speedo wouldn't even work if it was the sensor at fault?

Ok to update, I have tried now a third set of clocks and a third ecu hicas unit and I am still getting heavy steering.

 

Does anyone here know for sure if ECUTALK software using a consult lead would display speed. I get every other reading except for speed, and the funny thing is the doner car I tried various bits from also had no speed reading using ECUTALK. I am either thinking the car has the same fault or ECUTALK dosnt support the speed signal from the ecu?

 

Many thanks

Maybe try using different software, the free version of conZult should do.

Just because your getting some form of signal from the speed sensor doesn't mean that it's performing within the parameters the ecu can understand.

 

Most logical explanation for the fault is the speed sensor (it is a common fault that gives the symptoms your experiencing) and you can't possibly eliminate it unless you either analyse it's pulses with an oscilloscope or replace it with a know good/new sensor

That would only be possible if the sensor generates two separate signals at different frequencies down the same wires, otherwise it'd need to be two separate circuits, one to the clocks, and the other to the control units. But if that was the case then converter chips wouldn't be able to trick the ecu to change the speed limiter. I'm happy to be proved wrong of course if it turns out to be that, but I'm not convinced from previous experience with Nissan speedometers.

Ok, Well I have tried everything else, so got to be worth a go.

 

Thanks

Maybe try using different software, the free version of conZult should do.

 

I had a copy of Conzult on a disc supplied with my lead but everytime I tried to run it I just got winscript error messages. Do you know if there is a downloadable version somewhere?

 

Thanks

Yeah, on Google mate. It'll surely be on it's own website. :)

Thanks Stuart.

 

Nick, in your experience could the speed sensor be faulty to cause my power steering failure but still give a good/accurate signal to the clocks?

 

Many thanks

Only if it generates two individual signals. If it does, it'd be covered in the relevant section of the workshop manual for testing the sensor. I'll have a look later on to see if I can confirm.

This section of the workshop manual suggests it only generates one signal, since the only check it says you can do is see if the voltage fluctuates as you rotate the pinion. Which it will be doing for your speedo to function. I still think it's a wiring problem since you've tried everything else.

 

How've you got on with trying conZult by the way? Just looked, and there's a download section on http://www.conzult.com.

Well I am getting a fluctuating voltage read up to and out of the clocks. I am also getting a steady voltage at the steering rack solenoid of about 5.5 volts when the steering is light, then as soon as the speed drops below 30mph it goes to 1.5 volts and stays there until I flick the ignition off and back on.

 

I am going for it again Tomorrow morning and will be looking for a speed reading using a downloaded version of Consult and will probably start to temporarily rewire the circuit.

 

It still seems odd to me that the problem only really started when I replaced my ECU as though maybe I have damaged some local wiring. But, that dosn't explain why I am still getting a matching fluctuation voltage at the plug from the clocks..

 

Many thanks

Dan

Fixed!

 

Many thanks for the help guys. Today I set about finding the problem and went through and double checked everything with a friend. We were at the stage to temporarily rewire the whole circuit. During a coffee break I found an old thread. Seems I have always had my consult adapter connected. I have unplugged it and done a good 20 miles with no problem. We also checked voltage from the steering rack solenoid and it constantly gets lower as the speed rises. With the adapter plugged in it stays at a steady 5.5 volts until it instantly drops to 1.5 when the steering gets heavy. There is no variation when it is plugged in.

 

The thread I found is linked below.

 

Once again many thanks for all your help and suggestions. Without it I would have given up and spent a fortune on diagnosing it.

 

 

http://www.300zx.co.uk/forums/showthread.php?178740-Ecutalk-plugged-in-and-unexpected-results

Interesting. Looks like that issue might be linked to a specific type or make of Consult adaptor. I've had 3: one from Rational Racing (no longer trading, I think), one a no-name from eBay and now my ECUTalk and none of those had this issue.

So thanks for the warning - good info if it happens to others.

It's one from eBay that says Nissan-14 on it. It reads lots of info but won't read speed and as I say has caused me my power steering issue when plugged in.

 

Thanks

Fixed!

 

Many thanks for the help guys. Today I set about finding the problem and went through and double checked everything with a friend. We were at the stage to temporarily rewire the whole circuit. During a coffee break I found an old thread. Seems I have always had my consult adapter connected. I have unplugged it and done a good 20 miles with no problem. We also checked voltage from the steering rack solenoid and it constantly gets lower as the speed rises. With the adapter plugged in it stays at a steady 5.5 volts until it instantly drops to 1.5 when the steering gets heavy. There is no variation when it is plugged in.

 

The thread I found is linked below.

 

Once again many thanks for all your help and suggestions. Without it I would have given up and spent a fortune on diagnosing it.

 

 

http://www.300zx.co.uk/forums/showthread.php?178740-Ecutalk-plugged-in-and-unexpected-results

Well that's a result! Well done mate, first I'd heard of a consult adapter blocking the speed signal to the various control units before!

That last line or two didn't make much sense, whoops. :)

 

So are you now using a different consult lead? I assume you'll now see a speed signal if using a different one. I wonder if it's faulty, or if simply all of that type do it?

I havnt tried a different lead. I will get one at some point. Thinking back it all makes sense. Post #42 the doner car had no speed signal either, and no doubt the steering would have gone heavy whilst it was plugged in if I got the car up to speed.