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alright, i did a quick search but couldn't find anything that had a solution to this problem

basically i did the check of the attessa system and it gave me fault code 21

this is noted as throttle sensor/circuit. now me being me, i'm not up to scratch with electrical systems

so i was wondering whats the fix for this problem?

whilst on my search i did come across something that claimed autronic systems can cause this problem but still no solution

any 2 cents is appreciated

thanks

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Grab a multimeter and check the resistance of the TPS at closed and at WOT. Should be 0.4v and 5V I think. If that checks out, then you need a wiring diagram and check the same but measured from the appropriate pins on the ECU plug. I'd do that with the ECU disconnected from the plug if I were you, just in case you find a way to fry the ECU with the multimeter! If you get a different result at the ECU end of the wires, then you have to find out why (ie, broken wire, or corrosion causing high resistance at a loom plug, etc).

Grab a multimeter and check the resistance of the TPS at closed and at WOT. Should be 0.4v and 5V I think. If that checks out, then you need a wiring diagram and check the same but measured from the appropriate pins on the ECU plug. I'd do that with the ECU disconnected from the plug if I were you, just in case you find a way to fry the ECU with the multimeter! If you get a different result at the ECU end of the wires, then you have to find out why (ie, broken wire, or corrosion causing high resistance at a loom plug, etc).

got the multimeter but not sure on where to put the probes ahah,

any help? new to skylines hey :S

have a power fc? sometimes they loose the throttle output to the attessa. first up check the tps voltage at idle. 0.4 is the norm.

nah autronic cdi, guessing itll be same type of problem,

is my plan to test this voltage but what point am i putting the multimeter probe?

you def need to bridge the tps signal wire to the attessa tps signal wire. (just join the 2 together)

cheers, when i work out where these two are, ill get to doing this, diagram i got from the workshop manual is a bit tricky/too blurry to figure out ahah

  • 12 years later...

If anyone else has this issue, check your alternator output. 
 

My car is used infrequently, so I trickle charge my car when it鈥檚 laid up. 

I had recently upgraded the radiator including a new electric thermo fan. 

The 4WD Light would come on after driving for a while, usually if it had got hot enough to activate the new thermo fan or if the A\C cut in. My alternator output was only 12.7v under load, so I have deduced that the battery was slowly discharging while driving and any sudden electrical load was enough of a voltage fluctuation to trigger the ATTESSA computer into thinking there was a fault. (Code 21)

Most people will find that they have added extra electrical load with upgrades/modifications over time which the original electrical system wasn鈥檛 designed for. 

I have upgraded to a ARD 150A Alternator from RHD Japan.

 https://www.rhdjapan.com/ard-low-resistance-high-output-alternator-z31-r31-r32-r33-r34-c34-c35-wc34.html

Problem solved. 

These are almost a straight fit, only modification is a larger electrical Lug is supplied and needs to be fitted to your wiring loom for the output side of the alternator. 

Cheers 

 

IMG_8671.jpeg

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