Ghost Shadow Posted October 31, 2011 Report Share Posted October 31, 2011 take the DEM off the car, see if crud comes out. my xc90 had aoc fluid inside it all on the circuit board. i used a razor blade and opened it up then resealed it with silicone. plus i had a dem 0007 and 0006 code Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 1, 2011 Author Report Share Posted November 1, 2011 Just to make sure I was doing everything correctly I went ahead and hooked up DiCE to my 2006 XC90 V8 AWD and was able to communicate successfully with the DEM and view it's live data. Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 1, 2011 Author Report Share Posted November 1, 2011 Im kinda at the end of my rope with this problem, it's basically already winter and i'm still in FWD. I tried to detect the AOC pump going today again and it's not running, I know cause I unhooked it and it sounded the same as when it's connected, I also unplugged it and tested the leads coming to it for voltage and there was none. It looks like the DEM is the fault here. I found this pdf for troubleshooting the DEM from XemodeX: http://www.xemodex.com/technologyimproved/DEM%20Diagnostic%20Flow%20Chart.pdf I just find it odd the DEM can die and not generate some fault code. Anybody have anything else they want to add before I bite the bullet and send it off to XemodeX Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 2, 2011 Author Report Share Posted November 2, 2011 I pulled the DEM today and am a bit confused by what I see and found out. I thought the sensors were supposed to be sticking out from the housing but mine looks different: Hooked up some 12v directly to the AOC pump and verified it does work: Interestingly enough, I scanned the car with DiCE with the DEM unplugged and found a CEM-1A64 DTC - Communication with AOC control module signal missing. This goes away once the DEM is plugged back in. When I read the Fault tracing for the 2002 AWD it doesn't say anything about LIVE DATA, just testing the circuits. The 2006 AWD Fault tracing goes into the process of accessing the Live Data..... I wonder if there is a difference between my version of Haldex and the newer ones that makes mine show white in VIDA?? Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 2, 2011 Author Report Share Posted November 2, 2011 Newer Haldex from 2003 onward for comparison: Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 2, 2011 Author Report Share Posted November 2, 2011 So it turns out that mine is a First Gen Haldex controller compared to the later Gen 3s. Look here: http://www.awdwiki.com/en/volvo/ , the 2002 S60 apparently comes with the First Gen Haldex system... http://www.awdwiki.com/en/haldex/ for more info about the generations... I'm curious if my e-brake could be playing a part here, it doesn't work right now and might be conflicting with the DEM??? Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 2, 2011 Author Report Share Posted November 2, 2011 Just spoke to Chris @ XemodeX and he really helped clear things up. Yes indeed we are looking at 1st Gen Haldex unit here. Based on the fact that it is getting power and ground, has network integrity, shows white in VIDA but throws a code when disconnected we can assume it's a fault on some module inside the controller. Something about a hi and lo side of the CAN network and a specific part of the DEM processor that is common to the 1st Gen Haldex unit. He says they have not been able to repair this particular failure mode because of it's extremely small and complicated nature. Good news is that you can simply swap in a another used controller in this year with no need for software updates. So I'm off to find another controller and give it a shot. Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 17, 2011 Author Report Share Posted November 17, 2011 Bought a low mileage complete rear carrier w/ DEM for $200 and swapped in the module. The clip was busted so I went ahead and joined it to the old connector and reinstalled. Still doesn't show live data in VIDA because 1st Gen Haldex don't do that. But when I tool it up the rainy, gravel driveway and boosted it didn't spin the front tires, no traction control lights, just pure AWD action. AWD works just fine again. yay! Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 23, 2011 Author Report Share Posted November 23, 2011 Okay this sucks, recent development as of this mornings commute to work: AWD doesn't work again. Ugg. It just spins the front tires in the rain, lots of torque steer and very little forward movement. I am thinking the AOC pump might be shorting out and drawing more voltage and burning up the DEMs? When I tested the pump to verify it worked I noticed it was kinda loud, I did not test the current draw though. Now I do have another AOC pump from the low mileage carrier sitting here. But I'm still going to be short a working DEM. I am thinking of opening the DEM and trying to see if it's visibly melted or burned up. I think Chris at Xemodex can repair the damage from the pump shorting anyways. When we spoke last he mentioned that there are certain failure modes we can fix and some which he can't. We were under the assumption the problem with my first DEM was in the communication network side of things because it wouldn't read in VIDA. After fixing the AWD by replacing the new DEM and seeing it still not read in VIDA we figured out the First Gen Haldex/DEM units do not show live data unlike the newer Gen 2 units. Since the new DEM failed after only a week we can assume it was due to the pump drawing too much current, in which case Christ should be able to repair both DEM units I have here. So lesson learned, when doing the intial trouble shooting for 1st Gen Haldex, make sure to not only test the pump for activation but also check it for current draw. This might prevent your new DEM from failing immediately. Link to comment Share on other sites More sharing options...
lookforjoe Posted November 23, 2011 Report Share Posted November 23, 2011 Hope you get it sorted out - sounds like you've covered quite a learning curve with this generation. Link to comment Share on other sites More sharing options...
JRL Posted November 23, 2011 Report Share Posted November 23, 2011 I had one with partial, intermittent AWD. It was a bad Haldex pessure sensor. Less than $80 for the part Link to comment Share on other sites More sharing options...
NJGreenBudd Posted November 23, 2011 Author Report Share Posted November 23, 2011 Lookforjoe, thanks man, we'll get it sorted out eventually but this was a disappointing setback with winter being so close. Part of my difficulty is the lack of information that pertains to this generation Haldex controller, much more info out there about the newer versions. JRL, was that a first gen Haldex controller or newer? I can't find any part #'s for pressure sensors for my year, when the DEM is taken off there are no sensors apparent unlike newer controllers where they are visible on the mating surface of the differential. I believe this year the sensors are integral to the controller. I'll update as we go along but the basic plan of attack is to swap the AOC oil pump for the lower mileage unit and then replace the DEM again with either another used unit or a rebuilt unit. Thanks and have a great day, NJGB Link to comment Share on other sites More sharing options...
winnipegtibook Posted January 25, 2012 Report Share Posted January 25, 2012 Anyone know where I can find the Tech-Net Note (TNN) 40-02? Link to comment Share on other sites More sharing options...
NJGreenBudd Posted January 27, 2012 Author Report Share Posted January 27, 2012 I might be able to upload it tonight for you. In related news, I have sourced another low mileage rear carrier complete with DEM, this one only has 45,000 miles and looks great, no damage, bolts are still shiny, etc.... I am going to actually swap the entire AOC section, split it from the final drive and save some time removing the whole assembly. I'm just waiting for the AOC gaskets to get here from Tasca and I'll post an update with pics of the swap. Link to comment Share on other sites More sharing options...
NJGreenBudd Posted February 3, 2012 Author Report Share Posted February 3, 2012 I'm sorry I don't think they have the tech notes in VIDA, unless I am missing them or not looking in the right place. Here's the AOC swap: Fixed the AWD again today. Hopefully for a longer period of time now that the entire AOC unit has been replaced. Drop the exhaust: Unhook the sway bar and push to side to release elevator bolt for rear carrier: Remove driveshaft: Make sure fluid fill plug is open / not stuck before draining assembly. loosen fill plug: Remove AOC to final drive bolts: Remove AOC assembly: AOC and Donor Rear Carrier: New OEM gasket on new AOC: Link to comment Share on other sites More sharing options...
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