Volvo wiring / electronics not great? [Unpopular opinion/Rant]

[nonsensical]

I know I'm relatively new to this forum, but have been a car guy for years, worked on all kinds of stuff, done engine conversions and custom wiring harnesses, etc... This 07 V70 2.5T (120k) is our second Volvo after we had a wonderful 850 5MT that got totaled when someone ran a red light a few years ago.

Anyhow... The V70 seems to get regularly touted as somewhat indestructible / goes forever wagon, but so far I'm not getting a great feeling about the repairability of the car -- it seems like Volvo used average or worse wiring (insulation, loom) and electronics and then made it somewhat difficult to replace modules when they do go bad (hundreds of dollars to clone a CEM that's prone to corrosion)... I have an intermittent left turn signal issue that on the face seems like it should be pretty straightforward, it's just a turn signal after all... However, despite swapping bulbs side to side, cleaning the stalk tracks, cleaning the bulb holders, it still persists. What is odd (if anyone has any suggestions) is that when it's fast blinking and I get the DIM message about "Left turn signal bulb out", NONE of the bulbs on that side flash, which seems to point to an issue upstream of the bulbs / holders / etc.

Also, I do have the VIDA/DiCE, and will scan codes again (haven't for some time), but it seems a little bit crazy that you need a dealer scan tool to diagnose what seem like even pretty basic issues. I have an 03 Mitsubishi Montero that runs and runs, and when it has a problem, the check engine light comes on with a code that indicates the problem, and you fix it and reset it with a generic code scanner and away you go. It's been through more moisture, mud, dust and dirt than this V70 would see in 10 lifetimes and yet, no issues with wiring or electronics. A quick search of the forums reveals lots of P2 problems with various modules, including being totally dead / slipping out of gear / etc. It seems like someone at Volvo just thought making everything a module would be a fun experiment without a lot of thought to troubleshooting the network itself, repairability, etc...

Apologies for the rant -- but having owned many cars over the years (some newer than the V70), from a myriad of manufacturers I've never felt this "in the dark" and somewhat vulnerable in terms of a module or network just taking a poo somewhere and stranding myself and my family... Am I alone in this? Is the P2 really deserving of being called indestructible? The 800 series seemed much more robust at least electronically?

[oragex]

Volvo has very good wiring for most part - but the one on top of the engine can get damaged from the heat. As for the modules, with the exception of the ABS unit, everything else is very strong However, there have been lots of problems with corrosion and water ingress: REM, CEM, PEM, DEM and so on. But the electronic part itself is very durable. My rant with these cars are actually the electric connectors, often times difficult to undo, japanese cars have them so easy to undo

As for the 'computerized' concept with their network, then yes, it's confusing and unfortunately it has been the trend of all car makers since 2000 on. Sometimes it helps, other times it causes confusion and even points to a good module

[chris11211]

A lot of the connections are slapped with the Ford label so the fault should lie on Ford. How does it compare to ford's models in the 2000's?

[nonsensical]

Thanks for the replies -- good to hear that some have confidence in the wiring... Will hook up the VIDA/DICE and see what I find out.

[SVO LOU]

Our 01 xc70 had a similar issue but on the right side, turned out to be the semi-common bad ground at the socket but I thought that was earlier models like mine, not yours. I just added another ground wire to the socket.
I'm not a big fan of the rear light circuit board thingies but you take the good with the bad I guess.

[BlackBart]

Apologies for the rant --
.... taking a poo somewhere and stranding myself and my family... Am I alone in this? Is the P2 really deserving of being called indestructible?

I acknowledge your rant, and have some of the same concerns. Three separate fuse panels, etc.

My '04 XC has only a couple of quirks, mostly the instrument panel clock running warp speed every time you start it. Just weird - doesn't affect operation. My neighbor had a '06 XC that looked nearly identical to mine. He had some module / electronics / no-start problem and a local non-Volvo mechanic said he couldn't figure it out. He took the $250 salvage value and sent it away, which I think was giving up.

[nonsensical]

I get the impression that bad grounds seem to be a common cause for mystery / intermittent electrical problems in these cars -- is it usually corrosion at the ground (branch) terminal, or are the terminals not making good contact through paint / primer / etc? Really appreciate the discussion so far.

[SuperHerman]

I hate to say it all cars have similar problems. BMW - yes, Audi - Yes, Range Rover - Yes, Subaru - Yes, Jaguar - Yes -- those are or were in my fleet. I have wiring looms in my BMWs that fall apart. Modules in trunks that get ruined because of flooding. Some of the things are comical.

Wiring ground straps are common failure points for ALL cars in the salt environment.

As far as European cars - the early 2000s were bad years. From biodegradable wiring harness to lead free solder caused many problems. After a few years they managed to get things right.

Regarding the various Volvo modules. Volvo has to protect its customers from theft, its intellectual property from theft, and make a system that is robust and safe. It is what it is and the same story is in every car I currently own.

Ford has excellent electronics as does GM - Toyota the same. They also have protected modules.

[nonsensical]

When I first saw this, I was a little taken aback:

[abscate]

Most of my problems in my 2005 have been caused by the DUM, installed above the left seat in the US market.