Dem communication problems

[Mick82]

Hi all new to the forum. I have a 2007 xc90 d5 185 bhp with 192000 having a problem with the dem module not communicating with vida just wondering if any body else had the same problem. Also the mechanic said it could be the pump but I've tested the pump when my original module went down and it was fine run 12v to it and it fired up but could a dodgy pump prevent Vida from communicating with it any advise would be gratefully appreciated thanks in advance.
Mick82 is offline

[Harvey]

Remove the module and check it for water ingress , There are number of firms that wil repair them so not Volvo dealer only.
and have a look at the plugs for corrosion.

[Mick82]

Hi Harvey put a new dem on it cleaned all plugs changed oil n filter checked for voltage to the pump got that powered the pump up with separate 12v supply that worked checked canbus high n low and got voltage over both pins but just won't communicate with vida

[davebb]

Hi Open up the Dice unit and make shore tall the leads are plugged in,
Dave

[Harvey]

Hi Harvey put a new dem on it cleaned all plugs changed oil n filter checked for voltage to the pump got that powered the pump up with separate 12v supply that worked checked canbus high n low and got voltage over both pins but just won't communicate with vida
where did you get the new dem from ?, was it brand-new or new to the car .
They are coded to the car but if you have the old unit the new one can be cloned from it.
you could also unplug the pump to see if the dem comes to life .

Just had a quick look fuse F27 & F23 on the REM are both good ?.

http://i1168.photobucket.com/albums/r499/harveysr/Mobile%20Uploads/2018-04/20180403_214424_zpskypmjfoi.jpg (http://s1168.photobucket.com/user/harveysr/media/Mobile%20Uploads/2018-04/20180403_214424_zpskypmjfoi.jpg.html)

[Mick82]

Got a recon 1 of a guy in London all software up to date but my original unit didn't communicate either everything works on the awd it's just not communicating

[Mick82]

Both fuses are good aswell

[Harvey]

whats the vida map screen look like for the dem red / grey / green ?

[Mick82]

whats the vida map screen look like for the dem red / grey / green ?

Not sure bud wife took it in I'm getting a Vida next week so I can look at it myself would the colour make a difference like?

[Ettienne]

Where abouts are you based? I’ve got a 2006 facelift dem from our old Xc90, if you wanted to rule it out.

[Mick82]

Doncaster

[Mick82]

The dem is working I think got no anti skid message does the pump run all the time or does it just kick in when it's needed? Traction control kicks in

[LeeT5]

Hi all new to the forum. I have a 2007 xc90 d5 185 bhp with 192000 having a problem with the dem module not communicating with vida just wondering if any body else had the same problem. Also the mechanic said it could be the pump but I've tested the pump when my original module went down and it was fine run 12v to it and it fired up but could a dodgy pump prevent Vida from communicating with it any advise would be gratefully appreciated thanks in advance.
Mick82 is offline

I'm assuming you can communicate with all other modules??


The dem is working I think got no anti skid message does the pump run all the time or does it just kick in when it's needed? Traction control kicks in

Traction control has nothing to do with the DEM. TRACS is controlled by the ABS module and wheel speed sensors.

If the DEM pump is not running, you'll know soon enough if you try to pull away quick in the wet.
The DEM pump runs all the time.

Haldex Gen 4 (which is fitted to your car) has an electronic pump which is constantly running as soon as you switch on the engine. Running a MAX pressure, full time!

Would help more if you could post the fault codes you have?

[Mick82]

I'm assuming you can communicate with all other modules??



Traction control has nothing to do with the DEM. TRACS is controlled by the ABS module and wheel speed sensors.

If the DEM pump is not running, you'll know soon enough if you try to pull away quick in the wet.
The DEM pump runs all the time.

Haldex Gen 4 (which is fitted to your car) has an electronic pump which is constantly running as soon as you switch on the engine. Running a MAX pressure, full time!

Would help more if you could post the fault codes you have?

I haven't got any fault codes it won't communicate

[LeeT5]

Was this a sudden fault or one that occurred immediately after fitting?

You do know it must have software loaded onto the DEM in order for it to communicate with the CEM?

[Mick82]

Was this a sudden fault or one that occurred immediately after fitting?

You do know it must have software loaded onto the DEM in order for it to communicate with the CEM?

Yes mate all software been done my original unit didn't communicate either

[Mick82]

I haven't got any fault codes it won't communicate

Also when u say it's nothing to do with trac when my original module went down front wheels used to spin up all time in wet but with the new dem it doesn't so surely it's got to have some sort of use within the system.

[LeeT5]

Also when u say it's nothing to do with trac when my original module went down front wheels used to spin up all time in wet but with the new dem it doesn't so surely it's got to have some sort of use within the system.

No. That just means the AWD is working as drive is going to the rear wheels, so no wheel spin.
Wet or dry, my wheels would spin when my DEM failed.

[LeeT5]

Not sure bud wife took it in I'm getting a Vida next week so I can look at it myself would the colour make a difference like?

Yes the colour makes a difference.

Red = Fault on that module / Recognised on CAN and communicating with VIDA/DICE.
Green = Everything is OK.
Grey = Module not recognised/no communication with VIDA/DICE.

[uqj83l]

I’ve just had a similar issue however I had fault codes BCM0094 and CEM1A64. I replaced the DEM (£140 Volvodiagnostic London), as the pump was getting 12V. However it turned out to be a lazy intermittent pump rather than a faulty DEM. I’ve asked Volvodiagnostic to return me my DEM (which was fine) or offer me a partial refund. I’ve had no response! Charming.
Good luck in getting it sorted. Both of my codes indicated there was no communication with DEM, yet DEM was fine.

[LeeT5]

Interesting.

When my DEM pump failed I had fault code DEM 0006.