C5 X7 tailgate anger......

[GiveMeABreak]

Ok, so hopefully once you have your unit connected we can read the fault code (s). I might be able to provide more info. But it will help if you can record the exact message you get that you mention above.

[Jetjockey]

So far three different diagnostic machines all read the same fault when connected, and that is:-
(0062 Cannot communicate with audio unit). Possibly the Lexia may read something different.
I’m just off upstairs to the “office” to install the Diagbox software onto the Laptop.

[GiveMeABreak]

Ok, but as I’ve mentioned somewhere, that many generic readers cannot read constructor ECU codes, so as long as the head unit ECU is receiving power, then Diagbox should be able to talk to it as long as the VCI is fully chipped.

Let’s see how it goes.

[Jetjockey]

Update.

Software installed successfully on the laptop complete with updates, however.......

Diagbox reports no “dialogue” with any car systems, so.......

It looks like a new version of the Lexia interface is needed.

[GiveMeABreak]

Yes, that one is missing the Optocouplers arrowed, and there will be other components on the other sides of the board including a 10k resisitor no doubt that is needed for full CAN communications.

[Jetjockey]

Thanks for that Marc.

My mate has now told me to keep the old Lexia but I don’t think it’s worth modifying. I could fit the optocouplers, used to be my job years ago, but I doubt I could justify the time taken to save a few quid.
In a new twist........ My mate came down and connected his Launch X431 diagnostic to my car, he then changed the Battery status monitoring from the Battery status unit to the BSI with no problems, so I’m now monitoring the “Economy mode” situation with interest. It’s bad enough the radio goes off when Economy mode activates, but when the powered tailgate won’t open..... Dohh!!
Interestingly, first thing this morning when he connected the Launch the Battery charge status unit was reporting only a 65% charge level. This does not bode well for the battery. Furthermore, despite having an 80Ah battery on the car, the options in the C5’s systems were only a showing selections available for 70 and 75 Ah batteries.

[GiveMeABreak]

Yes same here - I bunged in a Bosch S6 AGM battery when I got mine and it's fine except the poxy economy mode after about a minute. I have the big NG4 Navidrive telematics unit, emergency services module and welcome seats that move to allow entry / exit for the driver - but regardless, eve on a fully charged battery it won't play nice - so that's why I changed control back to the BSI.

The Battery Charge Status Unit is understandable if you are in Siberia with no breakdown service and want to be assured of starting, but good for diddly over here armed with 4 bags of shopping and a tailgate that won't open.

[Jetjockey]

Update. So far so good, the C5 now takes a lot longer to enter economy mode, the powered tailgate Is no longer a pain in the backside.

What would be really nice would be to add the 80Ah battery to the list already available in the car. I wonder can that be done and where that information is stored?

[GiveMeABreak]

No, can't be done - the entries are determined by the BSI software version.

[Rob Cox]

I've just used your Economy mode fix with my diagbox, worked a treat, thank you very much. Rob Cox Nottingham

[GiveMeABreak]

No worries - Just be mindful and keep you battery in good condition and you should be fine.

[Tomukas]

So how to fix that economy mode? Can sameone to show step by step?

[GiveMeABreak]

viewtopic.php?t=60776

[Lenny]

I finally did my 'Economy Mode fix' today.
Piece of cake to do thanks to the instructions, ta very much.

I'll see how it goes and report back.

[GiveMeABreak]

No problem, just make sure you keep your battery in good condition as you'll now have fallen back to the older system, so don't want to get caught out.