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4wd Light On Dash Of M35

Commsman

By Commsman,
in Four Door Family & Wagoneers

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Commsman Veteran

Commsman

Posted
Posted

Hi guys

the 4WD light on the RHS of the M35 dash - what does it mean when it's on? Is that normal or a fault situation?

I bought a GReddy infometer the other day and of course with my luck, it didn't just work when it was plugged in ;) .

Works great on my daughter's Micra though....

The culprit is a wire that was removed from the OBD2 connector that the meter plugs into. This wire has been taken out and plugged into another wire (heading into the dark under dash) by a previous owner.

I disconnected it and only drove the car for about 50m before I realised it felt like when the snow button is engaged, ie I could feel the front diff working. When I looked the 4WD light was on. Stopped the car, plugged the rogue wire back into its aftermarket connector and the light went out and the car drove like "normal", ie feels like RWD.

I would like to confirm if the light is on for all/most people and if what I have is essentially a way to make the car RWD. If that's the case it's easy to rectify and get my new meter working.

Thanks, Leon.

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andy65b Veteran

andy65b

Posted
Posted
Hi guys

the 4WD light on the RHS of the M35 dash - what does it mean when it's on? Is that normal or a fault situation?

I bought a GReddy infometer the other day and of course with my luck, it didn't just work when it was plugged in ;) .

Works great on my daughter's Micra though....

The culprit is a wire that was removed from the OBD2 connector that the meter plugs into. This wire has been taken out and plugged into another wire (heading into the dark under dash) by a previous owner.

I disconnected it and only drove the car for about 50m before I realised it felt like when the snow button is engaged, ie I could feel the front diff working. When I looked the 4WD light was on. Stopped the car, plugged the rogue wire back into its aftermarket connector and the light went out and the car drove like "normal", ie feels like RWD.

I would like to confirm if the light is on for all/most people and if what I have is essentially a way to make the car RWD. If that's the case it's easy to rectify and get my new meter working.

Thanks, Leon.

Hi Leon

the 4WD light only comes on in the process of starting my car. It goes off as soon as it starts and does not turn on again, not even with the Snow or Syncro modes engaged.

Sounds like you may have a device to split the drive front to rear.

Cheers

Andy

PN-Mad Grand Master

PN-Mad

Posted
Posted

We I can only go from my experience, and I have a different 4wd system to you. When I pop the fuse out of mine (I guess its the same thing as you disconnecting the wire) I get the same outcome with the 4wd light. 50 mts down the road it pops on. HOWEVER I have the opposite effect. when the fuse is pulled the car puts up the 4wd light, and the car only operates in RWD.

So for me- 4wd light = FAULT, and your only getting 2wd

I don't know if that'll help you at all. maybe you'll have to put the whole thing on stands, or a hoist, and figure it out.

bbenny Mentor

bbenny

Posted
Posted

Yeah mine sometimes comes on. When its on the car is rwd. Usually I just turn the ignition off and then on again and the light is gone and its 4wd.

Most common problem is low 4wd fluid in the attessa system. just pop the little box out of the right hand side of your boot and check.

It uses a synthetic transmission fluid i beleive.

Ben.

Commsman Veteran

Commsman

Posted
  • Author
Posted
We I can only go from my experience, and I have a different 4wd system to you. When I pop the fuse out of mine (I guess its the same thing as you disconnecting the wire) I get the same outcome with the 4wd light. 50 mts down the road it pops on. HOWEVER I have the opposite effect. when the fuse is pulled the car puts up the 4wd light, and the car only operates in RWD.

So for me- 4wd light = FAULT, and your only getting 2wd

I don't know if that'll help you at all. maybe you'll have to put the whole thing on stands, or a hoist, and figure it out.

Thanks Andy and Alex.

So discounting some small difference to 4WD systems between models, it seems 4WD light on = fault.

It's funny that, in Alex's case, light on = RWD and I felt that the car seemed to operate in snow mode with my light on and with the light off seems to be RWD....

Maybe the previous owners' mod was two fold; 1) make car perform essentially in RWD & 2) keep the light off.

Anyway, thanks for your replies. They have been very helpful.

I'm going to T off this wire and put a connection back into the OBD2 connector to get my InfoMeter working and thus leave the car performing as it was.

Next chance I get to have the car up on stands I'll see exactly what happens with & without the wire connected.

Cheers for that, Leon.

Commsman Veteran

Commsman

Posted
  • Author
Posted
Yeah mine sometimes comes on. When its on the car is rwd. Usually I just turn the ignition off and then on again and the light is gone and its 4wd.

Most common problem is low 4wd fluid in the attessa system. just pop the little box out of the right hand side of your boot and check.

It uses a synthetic transmission fluid i beleive.

Ben.

Thanks Ben, fluid levels are all good.

I'm pretty sure this is an electrical/electronic modification and does seem counter intuitive, given what I feel and what the light is doing. ie light on = 4WD, light off = 2WD.

Also worthy of note, when I use the snow button I don't get the orange 4WD light, just the green "locked differential" looking light.

Is that what you get?

Cheers, Leon.

zei20l Grand Master

zei20l

Posted
Posted

mine does it too, i also turn ignition off and back on again to clear the problem.

yes the 4WD light being on means there IS a problem. the green (orange on ours) 'sync' light is normal during snow and sync modes.

now if only i could get rid of the check engine light on mine lol

PN-Mad Grand Master

PN-Mad

Posted
Posted (edited)
It's funny that, in Alex's case, light on = RWD and I felt that the car seemed to operate in snow mode with my light on and with the light off seems to be RWD....

Maybe the previous owners' mod was two fold; 1) make car perform essentially in RWD & 2) keep the light off.

Its going to be pretty easy to tell if it is just rwd... Since you have an open diff/no LSD, plant it at low speed in the wet /low grip situation. If that rear inside wheel lights up, then your rwd. Thats what I found. If it hooks up and storms away, then your awd-ing.

In rwd, mine will just spin it forever... bit sad really, needs a LSD. But in awd, it will allow for a little chirp in the rear, and then just hooks up and shoots away.

edit- in safe and private area only.... don't be stupid :(

Edited by PN-Mad
Commsman Veteran

Commsman

Posted
  • Author
Posted
Its going to be pretty easy to tell if it is just rwd... Since you have an open diff/no LSD, plant it at low speed in the wet /low grip situation. If that rear inside wheel lights up, then your rwd. Thats what I found. If it hooks up and storms away, then your awd-ing.

In rwd, mine will just spin it forever... bit sad really, needs a LSD. But in awd, it will allow for a little chirp in the rear, and then just hooks up and shoots away.

edit- in safe and private area only.... don't be stupid :)

I'm always safe :(

Well, I bought an old OBD2 connectror from a wrecker and butchered it to remove one of the pins. After splicing it into the "special loop" that mine has and putting the pin in the connector where I believe it should go (pin 14) my new InfoMeter works properly and the 4WD light remains off.

Re real wheel spinning in the wet (RWD only mode), I've NOT been able to acheive that. Is it because your car has more torque down low than mine? I think the turbo motors are limited in 1st gear.

Either that or I am running in full 4WD mode. But that doesn't agree with what I feel when I pull the connector, which is the same as pushing the snow button.

I think your suggestion of putting it up on stands will be the only conclusive way of telling.

Cheers, Leon.

PN-Mad Grand Master

PN-Mad

Posted
Posted

My datsun with about 3 donkey powers could light a rear wheel in the wet. Come on, if its rwd, you really should be able to get some slip.

Iain, I'll let you know when I had it on the dyno, it had a perfectly flat torque curve thank you very much. You keep on talking but all I can hear is Lag... and a farting noise from a blocked BOV. :/

zei20l Grand Master

zei20l

Posted
Posted

my BOV is fine thanks mate :(

actually it not :banana: lol

i had a failed suspension install attempt last week so i wont be making it to this weeks thursday meet. when the suspension is done, ill come along!

zei20l Grand Master

zei20l

Posted
Posted

haha i didnt have my trolley jack so i couldnt get one end of the car in the air, only one corner. the sway bar prevented the strut from dropping far enough for me to remove the old one and replace with new one

also didnt have a socket large enough to remove the bolts that hold the brake caliper bracked onto the knuckle :(

i now have my trolley jack back, and ill be buying more sockets! just need to find a day to do all this crap!

  • 5 months later...
Commsman Veteran

Commsman

Posted
  • Author
Posted (edited)

Well done Leon..

There must be an aftermarket controller on your car some where to alter the front / rear torque split.

Cheers

Andy

I'm reviving an old thread of mine that I found when searching for info on torque split controllers.

I've had most of my dash out a number of times in recent months & not come across anything resembling an aftermarket controller.

Since changing the exhaust (& with some km's for the ECU to learn new parameters) the rear tyres are lighting up too easily for what I think a full 4WD system should allow.

Is this what others have found and I'm expecting too much from my attessa or should I not be able to do this with just an exhaust change?

Was wondering if the torque split controllers sold on E-bay for GTRs and C34's work on M35's? (Might just ask the seller & see if he knows.)

As fun as it can be, I really need more front & less rear torque.

Edited by Commsman
andy65b Veteran

andy65b

Posted
Posted

In the dry it is not possible to spin the rears unless going around a corner but in the WET, that is another story. I can regularly get the rears to spin in 1st mostly as the revs build through 2800 - 3300rpm and then the fronts grab and the car hauls away.

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