Oh my god i could cry lol. Just spent a fortune getting the car ready for its MOT next week, and on my way home from work the speedometer has just dropped to 0, no twitching or anything, just dead.

 

Any advice? :cry:

hows the power steering??? if its ok then its more then likely the speedo circuit board they get dry solder joints on the circuit board . take the dial cluster out. remove the speedo section and resolder carefully all the joints.

i was afraid that was going to be the case lol. how about if the power steering isnt working? its a straight road i take home so havent really noticed.

i was afraid that was going to be the case lol. how about if the power steering isnt working? its a straight road i take home so havent really noticed.

 

power steering intermittant or just heavy can be the speed sensor on the gearbox, easiest and cheapest is to resolder the joints on the speedo, it hasnt cost you anything other then time then. :)

true i suppose. Fingers crossed!!

 

Thank you!

Edited May 22, 200916 yr by Spealtrong
Forgot my manners :-P

most likely Speed Sensor became grubby or loose! Id do that 1st before soldering!

if the PAS is unchanged then its mostly likely dry joints on the speedometer circuit. If the PAS has gone heavy then its often the speed sensor itself or if you have a KPH>MPH convertor these are a common failure.

 

Unless your journey home did not require you to move your steering wheel at all then you would notice lack of PAS, its a heavy car without it.

The speedo isnt part of an MOT check.

The speedo isnt part of an MOT check.

 

No, only class 5, and 7

Cool because i dont think ill get it fixed in time lol. Im using my Tomtom at the moment and going by the revs vs gears to work out my speed lol. Yea it has a kph/mph convertor.

 

Ill be looking into it today so ill let ya all know what it turned out to be.

Ok, heres what happened:

 

1) Took the dash apart and check for loose/broken connections and couldnt find any. Didnt really fancy stripping the clocks down to resolder as i would end up braking them (i have no patience lol), so first thing i did was snip all the wires to the kmh/mph convertor and wire it direct to the speedometer (so it would be back in kph).

 

2) took it for a test drive. No luck

 

3) wired the convertor back in and cleaned up some connections

 

4) took it for a test drive, however on the way back the powersteering stopped working

 

so now i need to check out the speed sensor/connections:-( i know its on the gearbox somewhere, just need to find it lol.

Yeah it's on the side of the gearbox.

If you need a new one speak to Mike at MJP he can get most Nissan parts much cheaper.

Where abouts in York are you? I'm in Harrogate.

Im in Wigginton so only about 30 mins away from harrogate. Only problem with Z's is that they are impossible to get under without car ramps or a pit :-( of which i have nither lol. In case cleaning it doesnt work, are they easy to replace with a new one or will it be a garage jobbie?

Im in Wigginton so only about 30 mins away from harrogate. Only problem with Z's is that they are impossible to get under without car ramps or a pit :-( of which i have nither lol. In case cleaning it doesnt work, are they easy to replace with a new one or will it be a garage jobbie?

 

They are a pain to get under.

Could do with a garage with a pit cos I'm fed up of jacking it up and putting it on stands every few days when something goes wrong LOL

They are dead easy to replace if you can get under the car.

Not sure if you need to take the exhaust off or if you get up the side of the box to unscrew it but it's not a big job either way.

Cool, ill give it a go myself then. I have a friend with a pit so ill just have to ask him nicely and maybe get him a pint.

Keep this in mind, might be the fix

 

http://www.300zx.co.uk/forums/showthread.php?t=122118&

ok so ive checked everything out (speed sensor etc) and all seems fine so the last remaining thing to do is to resolder the the dial, i was going to do it this afternoon but then this happened....

 

I was driving back from a friends house when the needle suddenly shot to 140mph, it stayed there for a few moments then went off the scale (180mph+), now the speedometer is working above 60mph, but invertedly, for example when i hit 60mph the clock drops down to 140mph, then as i go faster the clock drops to about 130mph respectively. but as soon as i drop below 60 it goes off the scale again, could this still be dry solder joints causing this?

 

I was driving back from a friends house when the needle suddenly shot to 140mph, it stayed there for a few moments then went off the scale (180mph+), now the speedometer is working above 60mph, but invertedly, for example when i hit 60mph the clock drops down to 140mph, then as i go faster the clock drops to about 130mph respectively. but as soon as i drop below 60 it goes off the scale again, could this still be dry solder joints causing this?

 

Exact same thing happened when my speed sensor went fella, do you know its working ok or guessing?

pretty much guessing, i had a local garage check it out but im not convinced they knew exactly what they were checking, i looked at the end cap on the speed sensor whilst they had it up and it looked ok. ill just replace the whole sensor and see if that fixes it....where do you get them from? lol.

Its also worth checking if it has a delimiter chip fitted that its not faulty.It will have 4 or 5 wires.A live/earth ,signal in and out and iirc a grey wire that would feed the ecu for autobox if its been connected.Try joining the signal in/out wires back up looping out the chip and see if that cures it.Your speedo will read again in kmh but will prove if the chips faulty.

Its also worth checking if it has a delimiter chip fitted that its not faulty.It will have 4 or 5 wires.A live/earth ,signal in and out and iirc a grey wire that would feed the ecu for autobox if its been connected.Try joining the signal in/out wires back up looping out the chip and see if that cures it.Your speedo will read again in kmh but will prove if the chips faulty.

 

Tried that and it didnt work, also lost power steering when i removed the chip. That was the only time i lost pas and it started working again as soon as i wired the chip back in, also the grey wire to the ECU goes no where and doesnt seem like it ever did.

 

EDIT: just re read about the autobox lol, mines a manual. I really should put it in my sig. Its a 91 NA manual.