4Wd Fault

[GimpyDammit]

OK,

Been having ongoing problems with the 4wd system in my R32 Gtr.

Normally, everything is fine.

Lights on and pressing brake pedal bring the 4wd light on. Checked ecu in the boot, 21 flashes.

Recently I got hold of a pfc hand controller, checked the tps signal. Was around 0.60v

While checking, I noticed that the tps voltage would go up when the lights were on and when brake pedal was pressed, i'm assuming that's not right.

Could be a grounding fault?

Anyone else had a fault like this?

[sydking]

Check the fauls code chart, I've posted them here before, I've jas no luck fixing mine, will ne tryin tps next

[GimpyDammit]

Code was 21, throttle sensor or circuit.

[Moodles2]

0.6 is maybe too high, 0.45v is where it should be at idle

[GimpyDammit]

Have adjusted it to 0.5, still faults with lights on

[GTR_JOEY]

exacty same thing happens to me

i found a couple of earths that were a bit dodgy and sanded it back... this did fix the problem for a while, but it came back again ,

If you figure it out for god sake let me know what it is lol

I find it does the same thing when u hold the power window buttons down when they are already down.. seems like it gets a large current draw and drops the awd for some reason

[GimpyDammit]

Where were the earths you found?

Yeah, mine does the same with the windows ><

[GTR_JOEY]

cleaned up the main battery earth

i also had some fookin weird custom earth job from the bloke before me the conected to the strut tower...

i think he had tried to fix the same problem by getting a new battery and alternator... obviously didnt help

Edited January 23, 2012 by GTR_JOEY

[GimpyDammit]

Interesting,

I'll have a go at the battery earth and see how it goes.

Its a funny fault, coz sometimes its fine and other times even with just the lights on the 4wd fails

[GTR_JOEY]

its a f#uckin pain in the arse is what it is...

pretty much cant drive at night and pull up to a set of lights without the awd dropping out

let us know how u go and if anyone else has any ideas it would be much appreciated

btw im also running a PFC, maybe that has somthing to do with it?

im changing to a LINK soon so we will find out!

Edited January 23, 2012 by GTR_JOEY

[GimpyDammit]

I'm running a pfc too

Random question, does your volt gauge more when you put your lights on or brake?

[GTR_JOEY]

Couldn't tell ya mate, haven't driven it for over 18 months as I've been rebuilding it

[jiffo]

Check your alternator is up to the job.

GTR's draw a lot of current, specially when the ATTESSA pump cuts in.

Most old GTR's have lost the charge in the accumulator so the ATTESSA pump runs way too much.

Add the wattage of headlights, stoplights, wipers and so on then see how much the alternator is pumping out on idle, you may be in for a shock.

Remember the alternator's rated output (90amps) is not at idle.

Mine couldn't keep up, ATTESSA light would come on periodically as it pumped up pressure.

Changed to 35W low beam HID's and that gave me enough headroom for everything to work OK.

Still it's a sign that in my case the original 21 year old alternator is getting a bit sad.

[GimpyDammit]

Was thinking that the alternator might b on the way out.

I have an rsm, boost controller and other bits running too. Maybe a bigger alternator could fix it