xc90 no rear wheel drive

[v70-xc90man]

I've got the same problem now no fault codes just fwd only, the propshaft turns with all four wheels off the ground but no rear wheels turn. when you turn the ignition on is the diff pump supposed to prime the oil pressure? So i should hear the pump with a ear to it when i turn the ignition on ? As i need to know if the pump is faulty how can i tell please ??

[Clan]

Originally Posted by v70-xc90man

I've got the same problem now no fault codes just fwd only, the propshaft turns with all four wheels off the ground but no rear wheels turn. when you turn the ignition on is the diff pump supposed to prime the oil pressure? So i should hear the pump with a ear to it when i turn the ignition on ? As i need to know if the pump is faulty how can i tell please ??

if all wheels are off the ground and you turn the propshaft the rear wheels wont turn but the front ones should ..

the pump does prime when you turn the ignition on .
On 2007 and later models the rear wheels drive from rest to get you going then disconnect until they are needed .
But Propshaft is ALWAYS connected directly to the front wheels if the splined angle gear sleeve is ok ..

[v70-xc90man]

Yes mines a 54 manual xc90 if i start the car and put in 1st gear with all four wheels off the ground the fronts turn and the propshaft but the rears wheels don't, i can't hear it prime the pump when the wife just turns the ignition on so must it be the pump ? As if the pressure switch was faulty would it stop the pump from priming first with ignition on do you think or can i Check with multimeter ? Do you know please what voltage the pump runs at many thanks

[Clan]

Originally Posted by v70-xc90man

Yes mines a 54 manual xc90 if i start the car and put in 1st gear with all four wheels off the ground the fronts turn and the propshaft but the rears wheels don't, i can't hear it prime the pump when the wife just turns the ignition on so must it be the pump ? As if the pressure switch was faulty would it stop the pump from priming first with ignition on do you think or can i Check with multimeter ? Do you know please what voltage the pump runs at many thanks

The pump is 12 volts and can be activated to test it by volvos diagnostic computer when connected to the car . The Oil pressure sensor inside which is part of the DEM electronic unit on the haldex can become faulty and an improved one is available , again . the volvo diagnostics can read and strored fault code .

you could unplug the pump and apply 12 volts and earth to it and see if it runs .