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Hey guys

Ive had the 4WD light coming on over the last week or so but intermittently. If the light doesn't come on everything works as per normal but when the light does come on it won't engage the 4WD at all although the car still drives as normal. Ive checked the fluid and gave it a bleed but no difference. I also tried a different relay thats located under the air box and made no difference within the quick 5min test. I also found out via Nissan this morning that that relay is not the attesa but the ABS relay and is available for $99.45 retail ex Japan. The strange part is though that the part number listed under NM35 is different to the number on my relay/ my relay part number doesn't exist according to Nissan.

I had an it scanned and it comes up with code "C1208 pressure switch" Does anyone know what the pressure switch is and exactly where its located?

Im leaning towards an electrical fault due to the fact that when the lights not on the attesa will engage the front drive as normal on heavy accel. It doesn't cycle and click the relay like Ive read some guys have a problem with if the accumulator is shagged. I have noticed though that I used to hear the pump give a cycle at times when Ive pulled up at traffic lights to pressurise the system but it no longer does this.

Appreciate any help with this pressure switch problem guys.

Cheers

Checked the connections at the pump. Look all good. The plug with 2 wires only has 4.7 volts to it with car off and running, would that be right?

When I first start the car I can hear the pump give a quick .5 sec pulse then a few seconds later another .5 sec pulse and then the 4WD comes on.

I did notice the gear indicator and odo lights in the dash cluster dim if I select syncro or snow and the pump pulses/chirps.

Yeah dim is more accurate then flicker. Sounds like similar issue I'm having. So you reckon its NOT the relay but this "pressure switch"?

The auto sparky said the code was for pressure switch, he didn't know what or where it is though.

I'm going to Ryan's tonight to swap relays between our cars to try and 100% eliminate that. It seems know one has actualy said where this pressure switch is and what it looks like or if it can be bought separate. I see plenty of mention about the pressure switch but no other info.

Hopefully when I sort this I can add some extra info for guys that end up with the same problem.

If only the m35 turbo came in rwd like my old c34. I never liked the attesa due to the problems and costs involved when something goes wrong.

I have exactly the same random 4wd issue and unfortunately have for years. I'm not a great fan of the car when the 4wd light is on in the wet. Even in the dry it behaves a little differently.

Same thing. Pump runs not long after startup, interior lights dim and then toss a coin if the light comes on or not. At its worst about 90% of the time but lately about 50%.

I once had a theory that holding the brake on at startup might fix it. Maybe it delays it. (not so sure if it actually makes any difference but it makes me feel better).

Seems strange that it happens early after startup - if the 4wd light doesn't come on initially, it then won't come on at all.

Does anyone know if the 3 relays near the Attessa pump have anything to do with it? (I did fiddle with these once and just created a 4wd and Hicas issue!)

Offering a reward to the first person to solve this.

pressure switch.. on the c34's it should be a little switch on the rear of the gearbox where your pump is connected to.

at least i am lead to believe that that little hose goes into a "pressure switch" which activates the attesa clutch pack.....

I once had a theory that holding the brake on at startup might fix it. Maybe it delays it. (not so sure if it actually makes any difference but it makes me feel better).

Seems strange that it happens early after startup - if the 4wd light doesn't come on initially, it then won't come on at all.

Craig has noted in the past that stalling up his car straight away after startup works for him. In which case I'd guess that it's a hydraulic thing.

Yeah I find if I start the car with my foot on the brake it's a lot less likely to throw up the 4WD light. I don't stall it up though. I thought that would increase the chance of a fault code in the ABS system combined with the fact that relay is for ABS but no codes came up.

I'm determined to sort it out as I hate having sh!t line this going on with my cars. Just hope it doesn't cost an arm and leg!

Yeah gave it a bleed yesterday by myself, no difference. I flushed a good 2 raguletto sauce jars amount out of it. Id assume that would be enough to get out any air that might have been in there. Last night I went to Ryan's and swapped relays again no difference. when Ryan started his car you could hear the pump start and pressurize the system, mine was doing that a week ago but now I only get 1 or 2 chirps from it. Just weird how the attessa still work fine if the light doesn't come on even though you still only hear a chirp from the pump.

I'm off to Nissan this morning to find what/where and how much the pressure sensor switch is.

Edited by slippylotion

Well I just back from Nissan. They can't find the pressure sensor switch and therefore assume its built into the pump assembly as the only parts available to replace are the accumulator and the pump assmb. The pump assmb only interchanges with the V35 VQ25DD, all other attessa pumps are different.

I had my Japanese mate search in Japanese if theres any other info but it only came up with heap of people having the same problem with the only fix being to replace the pump assmb.

Its looking like Ill rip out the attessa all together and all problems solved.

Edited by slippylotion

Well I just back from Nissan. They can't find the pressure sensor switch and therefore assume its built into the pump assembly as the only parts available to replace are the accumulator and the pump assmb. The pump assmb only interchanges with the V35 VQ25DD, all other attessa pumps are different.

I had my Japanese mate search in Japanese if theres any other info but it only came up with heap of people having the same problem with the only fix being to replace the pump assmb.

Its looking like Ill rip out the attessa all together and all problems solved.

Damn...how much is this gonna cost?

5k trade price.

Problem solved now. Found a workshop in Sydney that can bench test and repair the pump assembly. Exchange unit for my worste case is $1495. Solenoid fix if everything else is ok, about $200. He said I can remove the pump and send to him and said its fine and safe to drive the car without it.

Can't believe you NSW guys didn't know about him.

I'll put his contact details up tonight in here and the M35 info page for others.

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