Modern cars, Arrghh!!
|Chris Crew||30/01/2022 21:51:45|
208 forum posts
The dashboard on my 2017 Volvo V90 recently lit up like a Christmas tree but the fault finally stabilised and indicated a failure of the rear lights. A quick check revealed that the lights on both the off-side rear and tailgate were not working. I immediately suspected a fuse and consulted the owners manual for the relevant information. Apparently, this car has three fuse boxes but nowhere is a fuse for the rear lights documented. Not only that, two of the fuse boxes do not appear to be in the positions indicated in the manual and there is no information on YouTube or Google that I can find that does not merely replicate the information I already have.
I have searched high and low for two of the fuse boxes to no avail, you would think that at least one could have been found, but no. There was a guy on YouTube hard wiring a dash cam into a fuse box under the passenger side foot well carpet on a V90 and you have to take the trim off the door pillar and console to get the carpet up to get at it which I did but there was no fuse box to be found on my car, but a fuse box under a carpet? - I ask you!!
I like to think that I am not exactly stupid when it comes to cars as, I suspect like many of us, I used to strip engines to fit new rings, fit end shells and change clutch plates etc. although I accept this is no longer necessary or even possible on the domestic premises. Whilst searching on YouTube I came across a campaign by American farmers demanding the Right-to-Repair John Deere agricultural machinery as they have the same problem with their modern tractors and combines as we do with newer cars. One man stated that when his old Allis-Chalmers broke down in the middle of harvesting he just got out his tool-kit and fixed it. Now he has to wait two days for the John Deere service agent to call. From the video, I got the impression this campaign is gathering pace and American farmers have a powerful political presence.
I fully understand their frustration as I have had to book the car into the Volvo service agent which will no doubt cost a small fortune for something that may be as simple as a fuse (hopefully) but knowing my luck it will probably be some mega-expensive electronic gizmo that will have to be ordered from Sweden, especially as the car had indicated various other faults before the lights failed. No wonder some people hanker for the old days!
|Clive Foster||30/01/2022 22:24:59|
|3137 forum posts|
Is this link of any help :- **LINK**
|Chris Crew||30/01/2022 22:40:59|
208 forum posts
Clive, Thank you for trying to help me but the information in the link only replicates that which I already have in the owner's manual. I have crawled all over this car, had trims off, carpets up, tried following what wiring looms I can find etc. all to no avail. I gave up in the end and booked it into the service agent. The last time a fault came up it indicated the start/stop (which out of habit I always cancel anyway) required maintenance. It cost ninety quid to get the fault diagnosed which turned out to be nothing more than a low voltage on one of the batteries because the car does very little mileage and is stood on the drive for days at a stretch. So it cost me £90 just to get the battery charged!
|J Hancock||30/01/2022 22:49:01|
|837 forum posts|
A similar type of fault recently occurred on my friend's newish 3.5 year old Quashquai.
A new battery cured it , even though absolutely no problems starting with the 'old' battery.
|563 forum posts|
You have actually checked the bulbs (and holder connections), Chris ?
|Jon Lawes||31/01/2022 09:02:41|
927 forum posts
My first thought was battery too. A lot of modern vehicle electrical systems are very intolerant of the high and low bus voltages that a failing battery can cause. The high voltage is usually due to the alternator trying to compensate for the failing battery.
|Chris Crew||31/01/2022 09:06:12|
208 forum posts
I haven't actually physically checked the bulbs, I suspected a fuse because half the lights are on the rear off-side wing and half are on the tailgate off-side so it must be something that is common to both circuits. I am not even sure if some of them are actually bulbs as it is difficult to see if they are not LED's given the length of the diffuser lens down the rear wing. The indicator is definitely a bulb, and working, and I think the tailgate light is a bulb but to actually get at everything looks to be such a kerfuffle, with trims and panels to be prised off etc. as the car is now booked into the service agent, and I am resigned to it costing me money, I think that I will leave the problem for them to sort out. Many thanks for your suggestion, anyway.
|Adrian R2||31/01/2022 09:09:53|
|164 forum posts|
Do you have a fault code reader? This has worked for me several times on my VW - plug in gizmo, get fault code, the free software I have explains some of them, others you have to do your own research. Best one was an intermittent misfire where the code pointed straight to a faulty connection in the cylinder head wiring loom, no way I would have found that otherwise. I would also check the tail light clusters for water ingress and corroded connections. Good luck!
1430 forum posts
Modern cars with stop/start have special batteries fitted, as I recently found out on my Honda Jazz, very expensive special batteries, if the battery is not in peak condition and fully charged then the stop/start will stop working. I only fitted my new battery a few weeks ago but already the stop/start has stopped working, probably because I only do short runs and the battery voltage drops off very quickly, I remember that the stop/start ceased working about two years before the battery finally failed, can only assume that the electronics in the car sense the battery charge and condition and stop the system selecting stop/start unless the operating parameters are met. Modern car electrics are vastly complicated compared to the electrical systems of cars that I first owned, my first car was a 1954 Ford Popular, a 6 volt system and as back up it had a starting handle, used frequently when it was cold and snowy and the battery couldn’t cope with the starter. Cars like the Volvo and my Honda are designed so that it’s virtually impossible to repair yourself and you have to use the agents, whose hourly rates for labour are frightening, Chris I wish you luck with your rear lights, would be interested to hear the outcome. Dave W
|Chris Crew||31/01/2022 09:27:36|
208 forum posts
Adrian, sadly I don't have anything so modern as a fault code reader, only a box full of old Sykes-Pickavant spring compressors and clutch aligners etc. from my youth when I was always having to repair cars just to be able to afford to run one in more impecunious times. I suspect a lot of us had to do that. I would not know where to start with modern diagnostic equipment although I did manage to extract a fault code, with a little guidance, from an ancient Astra estate that I was running as a van prior to retirement. Turned out to be the 'fly-by-wire' accelerator pedal which cost me £5 from a scrapyard to replace. As I have stated earlier, I think I will leave any further work to the service agent as I would probably end up doing more harm than good ripping panels and trim off not really knowing what I would be actually looking for. Your comments are appreciated none the less.
|kevin laxon||31/01/2022 09:50:56|
|15 forum posts|
I dought it will be a fuse ,I would think it will be either tailgate wiring or possibly moisture failing that it could be a Can Bus fault between the control ECU & slave unit in the boot,I would personally start by disconecting the battery for 10 mins then re-connecting(at your risk) & dont leave the keys in the car at the time & you may need a radio code !!.
p.s. there may be a given procedure for this in the handbook.
Edited By kevin laxon on 31/01/2022 10:16:40
|John Doe 2||31/01/2022 09:51:43|
86 forum posts
Chris, you can get vehicle wiring diagrams and locations of components. You will have to pay, but it will be a lot less than £90. (I realise this information is too late for this fault of yours but might be useful in the future).
If you have a minute, check this out:
(If we are not allowed to post links to youtube, please accept my apologies Mods).
Eric Obrochta is a really clever and genuine guy and he fixes cars at South Main Auto, near New York. He looks and sounds gruff, but don't be fooled, he is a really clever and honest guy. He can do everything on a car from air hammering off a rusty wheel bearing, to diagnosing complex electrical faults using oscilloscopes. He gets his wiring diagrams from an online subscription service. You can sign up for a day, a week, a month etc and download all the diags you need.
And his videos are very well made - he is quiet and informative, with no mucking about or annoying editing that you see on some youtube videos.
Coincidentally, Eric O's latest video shows a fault similar to yours (but not on a Volvo), which he traced to a faulty side marker light with a rusted connector that was dragging the volts down so the car 'brain' turned that circuit off. So your fault might not have been a traditional fuse.
Edited By John Doe 2 on 31/01/2022 09:54:07
Edited By John Doe 2 on 31/01/2022 09:58:29
|Andrew Tinsley||31/01/2022 09:52:13|
|1630 forum posts|
Volvo have never been the same since the Chinese takeover.
|Jon Lawes||31/01/2022 09:59:07|
927 forum posts
I would wholeheartedly disagree with your opinion there. I've had Volvos on and off for twenty years and they have been excellent (when I've gone off piste to other brands I've regretted it). Maybe a slight dip in the ford years, but the cars they are putting out now are class leading. I recently had an XC40 written off (due to a stupid error on my part) and couldn't find anything else even close to the quality, so I've ordered another. Chinese backed or otherwise, you don't get Car of the Year for pumping out kinder eggs.
|Peter G. Shaw||31/01/2022 10:05:15|
1421 forum posts
I have had similar problems with cars considerably older than 2017. In one case, where the car was misfiring, the mechanic looked for fuseboxes and found one hidden behind a panel in the glove box. Ultimately, that problem turned out to be a faulty fuel shut off valve on the carburettor.
But the one that really got my goat, was on a 2007 diesel Focus which was suffering from misfiring under load at highish rpm. My local independant couldn't find it so sent it off to a Ford main dealer where for the sum of about £90, an electronic diagnosis was performed, the result being a collapsed fuel filter costing about £30. Needless to say I was less than impressed at having fork out £120 for something that previously would have most likely been found the easy, but old-fashioned way, and relatively cheaply at that.
Yours disgusted of Tonbridge Wells!
Peter G. Shaw
|Chris Crew||31/01/2022 10:18:45|
208 forum posts
Kevin & John, Thank you both for the information. Although I spent a lifetime in the telecoms industry, at one stage of the technology I carried an oscilloscope in one hand and an AVO in the other which was a big leap up from the 50V test lamp on the old Strowger equipment, I am still fundamentally 'mechanically minded' and modern technological advances seem to have left me behind. I think that I am now too much of an 'old dog' to be taught new tricks because I am constantly amazed at what even modern smart phones can do. For instance, last week I was fumbling about with a tape measuring up a bathroom for renovation. The woman who was watching me said, 'oh! we don't do it like that anymore'. She took out her smart phone, fired up an app, pointed it at the datum points to be measured and the damned thing read out the dimensions in both metric and imperial. I was both amazed at the technology and embarrassed that I knew nothing of it, even though it had been supplied with something as ubiquitous as a mobile phone. I think I will leave everything to the Volvo service agent and hang the expense!
|Peter G. Shaw||31/01/2022 10:36:56|
1421 forum posts
Like you, I had a career in the telecoms industry, using the test lamp, Avo (or equivalent) and oscilloscopes. And in a similar manner to you, I too don't know what modern smart 'phones are capable of. But, quite frankly, I don't care. I don't want to know. My tape measure will still be working when the smart (ha ha) 'phone has failed. And lets face it, when measuring a bathroom, does it really matter if it's 86.189 feet? Or perhaps I should say 86.189 mm? Frankly it doesn't matter a damn.
The problem is that because the human race can now measure to incredibly small distances, or if you like given our respective ex-jobs, micro-volts, people think that they have to. A moments thought will show that in the vast majority of instances it just isn't necessary. Ok, perhaps you are calculating the amount of paint required to redecorate the bathroom. But when paint comes in 1ltr or 1/2 ltr tins, then what's the point in calculating to 4.078 litres when you will need to buy 5 ltrs?
Maybe I'm just a Luddite!
Peter G. Shaw
|Dave Halford||31/01/2022 10:51:29|
|2054 forum posts|
OBD 2 readers are both generic work on engines 20years old and cheap enough, however they only work on the engine systems. Anything else like lighting or traction control etc is maker specific and costs an arm and a leg.
|Adrian R2||31/01/2022 11:00:29|
|164 forum posts|
I use the freeware version of VCDS from Ross-Tech - works for pre-2006 VW and Audi. It does more than engines. They have newer software for later VAG vehicles but I haven't needed to try that.
Edit: For me this is a good approach to "right to repair" - i.e. the software allows me as vehicle owner to know what the fault is and to choose how it is repaired. If/when I eventually have to replace the VW I will look for something that also allows this.
Edited By Adrian R2 on 31/01/2022 11:04:22
|john halfpenny||31/01/2022 11:01:13|
|236 forum posts|
No longer true Dave. Inexpensive readers are available (£50 for my air suspended 2005 Land Rover) that will read and adjust everything via a smart phone. I think german cars are more problematic. Of course it's possible to cause havoc if you are not careful. We have to get with the programme, or stick with Morris Minors, or maybe a horse and cart.
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