bizarre power and engine failure 2004 XC90

bradnight · Post by **bradnight** » 02 Sep 2008, 12:53

I am wondering if anyone else has heard of this problem and solution. On a 6 hour drive to Los Angeles, my 69,000 miles, 2004 Volvo XC 90 experienced a severe "thump" in the front end, which was then followed by a very brief (split second) internal (meaning dashboard lights, hi-fi, dome lights, etc) power failure. Initially, the power failure would last only a split second and then car would continue running as normal, and there we no error codes or check engine lights. This happened as many as five times in a 6 hour drive.

But on the last long drive home, the "thump" was harder than usual, and the lights internally completely went out, hazard lights could not be turned on, blinkers could not be switched on, hi-fi went out, etc (though the electric windows would work).

I pulled over, and turned the car off and restarted it, and the yellow exclamation point dashboard icon/alert lit up, and a service message flashed referring to the anti-lock brake failure, and that the SRS needed to be checked.

This problem has been occuring for a couple of months, and is very intermittent. Before this last incident, I took it into the dealership in Los Angeles, who could not figure it out,. Now that I have an error code, I have it at another dealership in Northern California, who seems equally mystified and have told me that they dont think the error code of check the SRS is going to fix the problem.

Does anyone have any helpful suggestions? The engine thump, followed by electical failure seems really weird, and when i search the internet, there doesn't seem to be anyone else that is having the same problem.

Any advice you can offer would be appreciated. Thx, Brad

Post by **MadeInJapan** » 02 Sep 2008, 15:27

No, I have not heard of it but it's as if you had a huge fatal error with your electricals....almost like the blue screen of death (BSOD) on a Windows based computer. The only thing I can think of is either bad grounding wires from your battery or electrical cut-out from your battery or charging system....check those grounding straps as well as corrosion on your battery terminals. Since your car is so heavily computer driven, a short out of the computer would cause the engine to abruptly stop and certainly, it could start right back again- and manifest itself like it was a big "thump" and at the same time turn other electrical components off. What I typed is just speculation but worth investigating. I agree that ABS wouldn't be the culprit unless you felt your brakes grabbing at the same time that this thump occurred.

bradnight · Post by **bradnight** » 02 Sep 2008, 15:49

thx MadeinJapan! I will check out the battery very closely. Its interesting, I looked all over the net, and couldnt find a similiar problem. The closest I have found is a posting that discusses the role of the Central Electronic Module. Any thoughts on whether that module may be failing? Brad

Post by **MadeInJapan** » 02 Sep 2008, 16:45

Brad,
They hardly ever fail....a hiccup in the electronic system however could cause a hiccup there. Another thought I had....could be your immobilizer acting up...it's also called the antenna ring...actually it's where your key goes into your ignition (at least it's this way on some other Volvo's including our V70- same model year). If you have a short there all sorts of strange things happen. One cause of issues with this (not a short) is if you have 2 keys for your car very near each other. The immobilizer antenna reads one key as an intruder while the other is in slot and causes your car to become nonfunctional (this could happen for a split second until the computer gets oriented again- thus the shut-down). Just a thought but is the other key riding in the car with you, close to the front- near the ignition key, or even on the same key ring?

bradnight · Post by **bradnight** » 02 Sep 2008, 17:42

Never thought about the immobilizer angle. Thx for the suggestion. We do have additional keys for the vehicle, but only one key was in the vehicle while we were traveling. Does the immobilizer turn off the fuel pump, or do you know how it reacts? For instance, I thought immobilizer's typically wouldn't allow the car to start, versus shutting down the car while it is moving. Thx for all your advice! Brad

Post by **MadeInJapan** » 02 Sep 2008, 17:53

You are correct, but I've heard of strange behaviors in other Volvo's that are already running when another key is close by. It was a thought that I think you can rule out. However, ignition issues still could be a problem...next time you're in your car and engine running, try jiggling your keys for kicks...let's rule out that whole assembly once and for all.

bradnight · Post by **bradnight** » 03 Sep 2008, 17:13

Quick Update - I was able to find on the internet two other cases where 2004 XC90's had experienced the same symptons that I had experienced. In both cases, the CEM was the culprit. I relayed that information to the service manager who was unable to reproduce the fault under normal operating conditions. So they called a Volvo Technician back East who recommended applying a heat source (a blow dryer) to the CEM while the vehicle is running. Sure enough, that reproduced the failure, and they were able to confirm that the CEM indeed had failed. I had purchased the "extended warranty" on this pre-owned vehicle, so I am hoping the cost of repair will be covered. Once I get a repair estimate I will post for anyone else who may run across this problem. Thx for the info, it certainly helped. Brad

Post by **MadeInJapan** » 03 Sep 2008, 20:04

Well, I'm glad you found the problem. Let's hope a CEM replacement fixes it and they don't hit your wallet too hard (that the warranty pays up). Let us know the outcome.

freeroses · Post by **freeroses** » 07 Jul 2009, 09:48

Would like to know what the resolution was for Bradnight. Was it the Central Electronic Module and what did it cost to repair?

Pierre51 · Post by **Pierre51** » 05 Oct 2009, 10:38

Hi all,
I have just experienced the same problem twice in the last 2 weeks. Brad explained it very well, and the techies at my Volvo dealership were equally mystified and unfortunately useless. After a second visit, they suspected that the CEM was the culprit but were only 70% sure( I wonder how they got to that percentage but that is another issue altogether)The cost of repair in Montreal is somewhere around $2500.00./$2,800.00

I have resisted so far to pay that much for only 70% certainty but I am afraid I may have to bite the bullit pretty soon.

What happen to you Brad? Has it solved your problem?
Thanks
Pierre