'05 V7 D5 Electrical issues & DTCs...
 

Really two questions:

1. How do I read the Volvo DTCs without paying a garage £75 or so...
2. How to identify cause of a "Power System Service Urgent" message (the red battery light also comes on at the same time)

The two questions are obviously related. This "Power System" message crops up randomly - it tends to go away if you switch off then restart the car, but then may crop again randomly. All electrics seem to work, except the HU850 radio and the centre console 12V socket are completely dead - the 12V outlets in the back are fine. The HU850, like most HU850s, is pretty much useless anyway as it really doesn't work well. It need a proper repair or junking. Aircon and everything else is good. I had the alternator tested (it's a refurbished one anyway so only 1 year old) and it's fine and the battery is charging as it should. The battery was also tested by a specialist car electrics place and found to be fine.

I have the common alarm system failure warning too - that is, I believe, a fairly simple issue of replacing the battery in the alarm under the offside front wheel arch.

So, I need to read the proper Volvo diagnostics to identify the faulty unit(s) and stop the irritating messages. Plus, it'd be good to get the 12V outlet going again as that is used for phone charging... Ideas on the HU850 welcome.

Also, the fuel cap lid sometimes doesn't unlock. Ah, well...

a number of options but basically it boils down to, get a decent fault reader, get VIDA, or find someone near you that has one of the above and ask them nicely if they don't mind helping you out

sounds like you have checked the usual stuff already ? but intermittant faults may not show up when someone's testing things so who knows

presumably you did check the centre console 12v socket with the ignition on? if so it's possible it just hasn't been reconnected at the rear after someone did a bit of fiddling

the alarm message may not be as simple a case as you might expect, in the past it was generally considered a straight forward new battery job but recently I've read posts where people have bought a number of 2nd hand units online and found them all junk when cut open. a fair chance your original unit is the same, the PCB all covered with battery juice and burnt out . you can still get the replacement alarm modules though albeit at the cost of near as dammit £200

fuel cap lock is reasonably straight forward, open up right side panel in boot, unbolt and remove lock, open up and cleanout / grease / check operation (and remember it only locks after 10mins unless someones changed the programming at some point)

I've been looking at VIDA units but they are £150+

If there's anyone around the Tunbridge Wells/Kent area that has one I can borrow/rent, it'd be much appreciated! It seems a bit bonkers to buy one just for this job...

Thanks!

fuses..
 

Hi nick,

with the HU850, do you have the amp under drivers seat?, could be yours has never worked but sound is not bad, one easy upgrade is to add a yatour which is a small box that appears as a 10cd player but can then play mp3 or hook up to bluetooth sources, there are some fuses on the dash end drivers side, can fwd some info but one is for the audio so worth a check its not blown..

fuse 10 is audio (20a fuse), fuse 11 is amplifier(30a fuse)

non genuine volvo alternator is the cause of the power service message the car will test and run fine but the message will remain iv come across this fault before..

Interesting - the replacement alternator was one of these:

https://www.ebay.co.uk/itm/263221020737

I would have thought that would be OK? I had an auto-electrician check both the battery & alternator and both were fine (13.5V when engine running).

I got & installed these at the same time, though I could see nothing wrong with the original tensioner it made sense to replace that whilst I was in there:

https://www.ebay.co.uk/itm/202136915903

good choice to replace aux belt and tensioner as failure of these part can wreck a d5 engine.did your old alternator fail as you replaced it? if you still have it might be worth getting it refurbed. as stuart says the 12v socket is only live with the ignition switched on check fuse first if ok check if its connected in the console.:regular_smile:

The alternator replacement requires you to return your old alternator for refurbishment & a partial refund - you don't get that one back. If you don't return it, the cost is much higher (they don't refund you anything).

I've had this car since 2005 - the radio used to be fine, but slowly died - the amp is fine as CDs used to play perfectly - it's the radio that's gone AWOL. Now, the HU850 doesn't even turn on - display is dark and no life there, so CD stopped too.

I've checked the fuses etc. for the 12V outlet and they're fine. Onwards!

Do you get a red warning triangle in the dash?

I would start by getting fault codes erased. I dont know if it stores the fault and pops up the error as a reminder. someone else could chime in on that.

Also WRT to radio, you may have a 12v but do you also get a ignition on signal on a different wire? not sure how these are wired but IME radios can have a separate 12v in or out when ignition switched on. Just some thoughts, someone else might know more on this point too.

In no particular order:
1. Check running voltage. Use multimeter with everything off but engine running, then switch everything on (blower, high beam etc) recheck running voltage with MM. should get 13.5 and no serious drop when everything on.
2. Check ground strap and terminal post at battery, clean.
3. Check positive connection in engine bay, undo clean refit (with batt disconnected).
4. Check engine earth strap at engine block and chassis. clean and refit.
5. Check and clean alternator connections

But clearing fault codes would be first step in case its just a left over reminder. Ive also seen a smaller separate mini fuse board up under the side of centre console where it meets dash (just in case you were looking at a different one). Again I might be wrong on these points but just for consideration in case they help or give a lightbulb moment.

Finally got a Vida system working with a real DiCE.

Enclosed is the snapshot after clearing codes and then doing the on/off/idle sequence and rereading....

Where to start!