General: DEM Repairs

[Mattwjj]

Had same problem with DEM. Car shuddered and then lost all power, lucky no car behind me or I would have been a goner. Went to Volvo Watford, told me DEM was faulty after charging me for diagnostic test but that they didn't know any more. Took DEM off and sent to BBA - great guys but couldn't fix it but at least told me problem, CAN data not running thru properly. More than Volvo themselves could do!
Ok cost of new DEM from Volvo in Sweden is £1500 plus £70 labour plus VAT so looking at close to £2000. Car only worth about £4000 so not commercially viable. Why it costs so much nobody knows - or is it a known problem and a cash-in?
Spoke to Cat in Volvo UK Customer Care who said she couldn't help because of age and mileage of car and I hadn't had it serviced by Volvo. Age is 2004, mileage is 95,000 miles, and servicing been done at regular intervals with all Volvo parts.
Then what happened next was astonishing, Cat said that to get 100,000 miles out of my Volvo was good usage! Well, that really summed up my feelings about Volvo. Their own people don't think their cars should necessarily last more than 100,000 miles. I asked if I could quote her on that and she agreed...
Time to buy something else - let's vote with our feet!!!!

[bobdabuilda]

Originally Posted by Mattwjj

Had same problem with DEM. Car shuddered and then lost all power, lucky no car behind me or I would have been a goner. Went to Volvo Watford, told me DEM was faulty after charging me for diagnostic test but that they didn't know any more. Took DEM off and sent to BBA - great guys but couldn't fix it but at least told me problem, CAN data not running thru properly. More than Volvo themselves could do!
Ok cost of new DEM from Volvo in Sweden is £1500 plus £70 labour plus VAT so looking at close to £2000. Car only worth about £4000 so not commercially viable. Why it costs so much nobody knows - or is it a known problem and a cash-in?
Spoke to Cat in Volvo UK Customer Care who said she couldn't help because of age and mileage of car and I hadn't had it serviced by Volvo. Age is 2004, mileage is 95,000 miles, and servicing been done at regular intervals with all Volvo parts.
Then what happened next was astonishing, Cat said that to get 100,000 miles out of my Volvo was good usage! Well, that really summed up my feelings about Volvo. Their own people don't think their cars should necessarily last more than 100,000 miles. I asked if I could quote her on that and she agreed...
Time to buy something else - let's vote with our feet!!!!

That is appalling Customer service. You should have reminded her that the world record mileage on a car is held by a volvo p1800 that is over 40 years old and has done nearly 3million miles! http://en.wikipedia.org/wiki/Volvo_P1800

No doubt she's a Vicky Pollardesque computer says no type.

[Frimley111R]

Hi All,

My sisters XC90 has this issue and I saw somewhere that a guy said that a control unit somewhere near the windscreen can get wet if the sunroof leaks and this causes the car to think it has a DEM failure. As my sister has just had this issue (through a badly fitted replacement screen) I want to check this out first. I can't find the thread but does anyone know where this other control unit is so that I can check it?

[andyKent]

Since this seems to be the DEM thread.....

.....I'm having trouble with the larger DEM clip - can't get it back on.... is there a trick anybody can advise?

Andy

[Acer]

Originally Posted by andyKent

Since this seems to be the DEM thread.....

.....I'm having trouble with the larger DEM clip - can't get it back on.... is there a trick anybody can advise?

Andy

I think some people on this thread have got confused between the CEM and DEM. One bloke talks about his car shuddering and losing all power due to a faulty DEM. I am pretty sure that a DEM can't do that!!!

Are you referring to your DEM as attached underneath the car towards the rear?

[Ducklakeview]

Originally Posted by Frimley111R

Hi All,

My sisters XC90 has this issue and I saw somewhere that a guy said that a control unit somewhere near the windscreen can get wet if the sunroof leaks and this causes the car to think it has a DEM failure. As my sister has just had this issue (through a badly fitted replacement screen) I want to check this out first. I can't find the thread but does anyone know where this other control unit is so that I can check it?

That'll be the CEM...

Originally Posted by andyKent

Since this seems to be the DEM thread.....

.....I'm having trouble with the larger DEM clip - can't get it back on.... is there a trick anybody can advise?

Andy

CEM again?

Mike

[Blackbird13]

Hi, I've joined this forum as a result of the problems and Volvo service obtained. I have a V70R and the car 'failed' with the same fault massages; 'Brake failure-stop safely'. I stopped, brakes appeared to be OK, restarted with message; 'antiskid system service required'. At home checked with basic OBD fault code reader to get several fault codes including speed sensor fault cct A. I phoned my local Volvo dealer for advice and was advised to bring the car in for full diagnosis, appointment made, and was told that the car would be safe to drive. The next time I went out with the car it failed; same brake failure warning, all instruments; speedo, rev counter, trip mileage, temp indication off, lights fully depressed, power steering 'reduced'. so I pulled in and stopped. When I switched ignition on again; message 'anti skid system requires service', but the car would not start. After 10 mins the car started but with the same problems and I got home in a reduced power 'limp home' mode. I used Volvo Assist and a mechanic attended to check out the car. He concluded that the car would have to go to a Volvo dealer for repair. The car was transported to Mill Garages. They informed me that on initial analysis they couldn't find fault, and that a minimum of 2 hrs (@ £125) would be required, and it could take longer. I (reluctantly) agreed. I did my own research, including this forum, and noticed the coincidence relating to DEM faults, also remembering that the attending technician had shown several DEM fault codes. I phoned Mill Garages the next day, intending to advise on my findings, but they told me they had found the fault; faulty DEM! Also advised that the replacement would cost £1525! Reluctantly I had to agree, almost a hostage situation, only way to get car back. Subsequent ally I was to find that the DEM could be repaired (£100)! When I went to collect car was billed for 3.5 hrs to find fault, (£461) programme module (£45.12). From my limited information, I had diagnosed the fault to be the DEM in under 1 hr! it took Volvo, with all their 'expertise' over 3 hours. I was not advised that the unit could be repaired. When I collected the car I raised these issues with the service manager. His response was that; they advise customers not to take to much credence of advise from on-line forums, and that I was lucky to relate it to a DEM fault, and Volvo do not repair or use repaired/refurbished components. Whilst I can commend Volvo Assist for their response in attending, at home, to my problems, the recovery of my car to Volvo dealer, and the supply of hire car, I feel that I have more than repaid that in my eventual bill; £1976.52.

[Tannaton]

Originally Posted by Blackbird13

Hi, I've joined this forum as a result of the problems and Volvo service obtained. I have a V70R and the car 'failed' with the same fault massages; 'Brake failure-stop safely'. I stopped, brakes appeared to be OK, restarted with message; 'antiskid system service required'. At home checked with basic OBD fault code reader to get several fault codes including speed sensor fault cct A. I phoned my local Volvo dealer for advice and was advised to bring the car in for full diagnosis, appointment made, and was told that the car would be safe to drive. The next time I went out with the car it failed; same brake failure warning, all instruments; speedo, rev counter, trip mileage, temp indication off, lights fully depressed, power steering 'reduced'. so I pulled in and stopped. When I switched ignition on again; message 'anti skid system requires service', but the car would not start. After 10 mins the car started but with the same problems and I got home in a reduced power 'limp home' mode. I used Volvo Assist and a mechanic attended to check out the car. He concluded that the car would have to go to a Volvo dealer for repair. The car was transported to Mill Garages. They informed me that on initial analysis they couldn't find fault, and that a minimum of 2 hrs (@ £125) would be required, and it could take longer. I (reluctantly) agreed. I did my own research, including this forum, and noticed the coincidence relating to DEM faults, also remembering that the attending technician had shown several DEM fault codes. I phoned Mill Garages the next day, intending to advise on my findings, but they told me they had found the fault; faulty DEM! Also advised that the replacement would cost £1525! Reluctantly I had to agree, almost a hostage situation, only way to get car back. Subsequent ally I was to find that the DEM could be repaired (£100)! When I went to collect car was billed for 3.5 hrs to find fault, (£461) programme module (£45.12). From my limited information, I had diagnosed the fault to be the DEM in under 1 hr! it took Volvo, with all their 'expertise' over 3 hours. I was not advised that the unit could be repaired. When I collected the car I raised these issues with the service manager. His response was that; they advise customers not to take to much credence of advise from on-line forums, and that I was lucky to relate it to a DEM fault, and Volvo do not repair or use repaired/refurbished components. Whilst I can commend Volvo Assist for their response in attending, at home, to my problems, the recovery of my car to Volvo dealer, and the supply of hire car, I feel that I have more than repaid that in my eventual bill; £1976.52.

Could you be confusing your DEM (differential electronic module) with your CEM (central electronic module)? The DEM has a simple job to do, it controls when power is feed to the rear wheels, it's part of the AWD system. It can cause a few weired faults but I don't think could stop to car from starting or affect the instruments/wipers. The CEM can cause chaos..... It controls a lot if the electrical systems including lights, wipers etc.

Whilst it is sometimes possible to repair these units at low cost, the Volvo dealer would always follow the manufacturer prescribed route which is to replace with new - they would rather have a reputation for being expensive but fixing things first time - if it was under warranty you would expect a new unit.

[KBB]

Originally Posted by Tannaton

Could you be confusing your DEM (differential electronic module) with your CEM (central electronic module)? The DEM has a simple job to do, it controls when power is feed to the rear wheels, it's part of the AWD system. It can cause a few weired faults but I don't think could stop to car from starting or affect the instruments/wipers. The CEM can cause chaos..... It controls a lot if the electrical systems including lights, wipers etc.

Whilst it is sometimes possible to repair these units at low cost, the Volvo dealer would always follow the manufacturer prescribed route which is to replace with new - they would rather have a reputation for being expensive but fixing things first time - if it was under warranty you would expect a new unit.

The DEM conforms part of the overall Dynamic stability control system. It communicate's with the BCM and the CEM via the CAN BUS. When the fault inside the DEM creates a BUS short to ground it pulls the entire Stability control network including the ABS module to ground killing communication and leading to the brake service warning being displayed. This fault will certainly be accompanied with U DTC codes appertaining to CAN BUS faults and often a failure to communicate with the ABS and the DEM via a scan tool. If after disconnecting the DEM the scan tool can communicate with the ABS module you have verified the fault with the DEM

[RoyMacDonald]

Originally Posted by Blackbird13

Hi, I've joined this forum as a result of the problems and Volvo service obtained. I have a V70R and the car 'failed' with the same fault massages; 'Brake failure-stop safely'. I stopped, brakes appeared to be OK, restarted with message; 'antiskid system service required'. At home checked with basic OBD fault code reader to get several fault codes including speed sensor fault cct A. I phoned my local Volvo dealer for advice and was advised to bring the car in for full diagnosis, appointment made, and was told that the car would be safe to drive. The next time I went out with the car it failed; same brake failure warning, all instruments; speedo, rev counter, trip mileage, temp indication off, lights fully depressed, power steering 'reduced'. so I pulled in and stopped. When I switched ignition on again; message 'anti skid system requires service', but the car would not start. After 10 mins the car started but with the same problems and I got home in a reduced power 'limp home' mode. I used Volvo Assist and a mechanic attended to check out the car. He concluded that the car would have to go to a Volvo dealer for repair. The car was transported to Mill Garages. They informed me that on initial analysis they couldn't find fault, and that a minimum of 2 hrs (@ £125) would be required, and it could take longer. I (reluctantly) agreed. I did my own research, including this forum, and noticed the coincidence relating to DEM faults, also remembering that the attending technician had shown several DEM fault codes. I phoned Mill Garages the next day, intending to advise on my findings, but they told me they had found the fault; faulty DEM! Also advised that the replacement would cost £1525! Reluctantly I had to agree, almost a hostage situation, only way to get car back. Subsequent ally I was to find that the DEM could be repaired (£100)! When I went to collect car was billed for 3.5 hrs to find fault, (£461) programme module (£45.12). From my limited information, I had diagnosed the fault to be the DEM in under 1 hr! it took Volvo, with all their 'expertise' over 3 hours. I was not advised that the unit could be repaired. When I collected the car I raised these issues with the service manager. His response was that; they advise customers not to take to much credence of advise from on-line forums, and that I was lucky to relate it to a DEM fault, and Volvo do not repair or use repaired/refurbished components. Whilst I can commend Volvo Assist for their response in attending, at home, to my problems, the recovery of my car to Volvo dealer, and the supply of hire car, I feel that I have more than repaid that in my eventual bill; £1976.52.

Nice you joined the forum, but you are posting in the wrong part, this section is for the Mark 1 XC90 in all it's variations. You will get more relevant replies in the V70 section. It makes sense to post your year model as well as Volvo have a policy of continuous improvement so every year is a bit different.

Hope your car is running well now.