4wd Not Working - R32 Gtr

[rmc02]

Guys,

My 4WD light is on and the 4WD is not working. The 4WD computer in the boot is giving code 21 throttle postion swicth as the problem. To date we have tried different throttle position switches, different 4WD computers and even different ECU's ( the signal from the throttle swicth runs through the ECU).

The voltage at the 4WD computer is 2.4 Volts should be 3.5volts using the switches earth. Using a direct earth to the car it is 4.0 volts.

At the ECU the voltage is 4.0 volts. We bypassed the wiring (both positive and earth) in the car directly from the ECU to the 4WD computer. Still had 2.5V. That was very weird.

Has anyone had this problem before. Any ideas on where to look?

[TurboX]

I assume you have checked the obvious like the fluid level and also bled the system in the correct procedure ( as in HPI no 58 ) ??

If so, ignore me

[N1GTR]

Have you checked the fuse boxES (not only the engine bay one)

Check the one above your right knee. The AWD fuse is top left from memory but it should say on the insert on the back of the cover

[Guest Variable]

Guys,

My 4WD light is on and the 4WD is not working. The 4WD computer in the boot is giving code 21 throttle postion swicth as the problem. To date we have tried different throttle position switches, different 4WD computers and even different ECU's ( the signal from the throttle swicth runs through the ECU).

The voltage at the 4WD computer is 2.4 Volts should be 3.5volts using the switches earth. Using a direct earth to the car it is 4.0 volts.

At the ECU the voltage is 4.0 volts. We bypassed the wiring (both positive and earth) in the car directly from the ECU to the 4WD computer. Still had 2.5V. That was very weird.

Has anyone had this problem before. Any ideas on where to look?

I had this once with the same error code as well - it turned out the ECU loom wasn't plugged into the power FC properly - wiggled the cable a bit and the error went away.

[Driftn 180]

i got the clutch changed today on my r32 gtr and when i turned on the car from their joint the 4wd light came on.

i thought id drive home and see if it turns off and it didnt, even after turning the car off and turning it back on. it didnt feel like the 4wd system was working.. could it be that they didnt top up the oil or not done properly and the powerfc has disabled the 4wd system? i'll have to take it back to them tomorrow. any other thoughts?

the clutch was changed from a completely stuffed twin plate to exedy button clutch and new lightweight flywheel.

[T04GTR]

sory dude... it shoult be 0.4 volts max

more like 0.37 to 0.41 volts.

just mesure it at the tps and adjust it accordinly.

ps... you mesuring the tps supply voltage. not the signal voltage lol

[T04GTR]

owwww. power fc :eek:

ok.. you need to join the tps signal OUTPUT wire onto the tps signal INPUT wire..

ie.. ive seen some power fc,s loosing its out put to the auto/attessa ecu (depending on the car)

just do a search for the pin outs. i cant remember them rite now :

[TBee]

Maybe you should get the 4wd system re-bled. Not 100% certain but i think if you change the clutch it can introduce air into the system and that could stuff up the 4wd.

[T04GTR]

if its giving code 21. it may not be a hydrolic issue

[jetman]

it's not a hyd problem!!!! code 21 is as you say a Throttle sensor or circuit problem. Check your out-put from the engine computer you are running at the computer end and then check the coresponding input at the ATTESSA computer.

In the manual on page CH-74 check the pins that they stipulate. if no out-put from eng computer, there's your problem. If no voltage/ signal at ATTESSA computer then wiring is the problem. If wiring is fine. change ATTESSA computer, or change back to original computer and see if this fixes it. if it does, then it might even just be the output signal of the eng computer.

If you have a copy of the manual, use it as it doesen't lie. If it is the wiring, i fell sorry for you as i know how long it takes to hunt down a split wire. think if there has there been any changes in the wiring that someone might have accidently cut or tapped into a wrong wire. has anything also been recently rewired???

If you dont have manual, i,m sure there is some where on this site you can get it.

Cheers. i hope it help, if any.