XSeries-forum

X5Sport wrote: ↑Mon Apr 13, 2020 5:41 pm With the IBS being in the main power charging circuitry which also includes the alternator, there may well be a possibility. I’m not discounting the alternator as a potential cause of this - though I’m puzzled as to which bit precisely.

These cars can be a nightmare to diagnose random/intermittent faults unless left strapped to test kit. Somewhere like a Bosch Autocentre may have the right code readers. Tricky of course under the current ‘limitations’. Annoyingly not everything creates a code, but it’s still probably worth doing. I think a main Dealer will charge around £100 for a diagnostic check.

I use the Carly system on all of mine (it uses a wireless dongle to Android/IOS tablets). You can also get hold of INPA and ISTA - you’ll need a computer to run them though. They’ll cost you about the same as a diagnostic check.

X5Sport wrote: ↑Mon Apr 13, 2020 9:35 pm As already said, the test cables were probably not rated for the 240A alternator output that these cars generate. It’s current that cooks cables, not voltage. If the test wires were thinner than the cable feeding the alternator, then that’s why they cooked! There’s a reason for the 12mm diameter power cable!

If the IBS says the battery is flat, then it will call maximum output from the alternator. These cars have serious electrical power draw due to the computers. My X6 draws over 60A doing nothing, hence the cars flattening their batteries in just 20 minutes with the ignition on and no engine.

Those of us (like me) who are electrical/electronics engineers know better than to stick a multimeter in circuit on a modern car unless it has a rating of 300A plus. We use current clamps that convert magnetic fields from the cable into a meter reading. No cooked wires or fritzed ammeters.

The alternator being hot 2 hours after use might be a clue, but if it’s running flat out charging the battery then it will be hot. Up to 240A is a lot of energy being generated and that means heat. Alternators are solid blocks of metal (iron and copper wire too, so they take a while to cool.

Do you know what voltages were being produced whilst the engine was running? You said 14V? Most E70s are fitted with AGM type batteries and charge at around 14.4V DC. The battery should show 12.8V fully charged and brand new - getting slightly lower with age or charge.

An Indy (especially a BMW one) should really have diagnostics kit too, so could read out the log. I know £118 sounds a lot, especially if they come back and say nothing shows up (we’ve all been there with modern cars, and it’s deeply frustrating), but it may be your only option at present. However, maybe there’s a Forum member close enough, even with Social Distancing, to help?

You said you don’t have Comfort Access, but do you have keyless ignition? Accidentally pressing the key buttons (such as in a pocket) will wake the car. I’ve noticed my 2-series doing it so the key it kept In an RFID wallet now. I’m just trying to eliminate all the simple options before money gets spent. It may be the alternator, but I’m just trying to think of anything else that could wake the car up. Bad door locks, bonnet catch, boot lid, anything plugged into a USB socket or 12V socket (those should power if with the car switched off), alarm system, ConnectedDrive (if used), non-standard kit plumbed into the electric somewhere?

I had a Road Angel connected to the glovebox USB port on the X6 and that caused an issue according to BMW. It was waking the car so I had to hard wire it into the 12V rather than use a USB cable.

X5Sport wrote: ↑Fri Apr 17, 2020 6:30 pm Glow plug control on a car that old is very common and is frequently caused by failing glowplugs. It should be a relatively simple job but is fiddly on the E70 because of where the controller is located below the inlet manifold meaning disassembly required to get to it. The BERU made module is about £80, the BMW badged one will be more.

What often happens is the plugs start to fail and cause the controller to fail. Without the system working your DPF cannot regenerate and will eventually clog. You don’t want to get into that position as DPFs are expensive (BMW want about £1,500 plus fitting).

I had new plugs (6 off) and a new controller last year and the bill would have been about £450 at an Indy. If (like mine) the plugs stick and snap, then the bill (like mine) will be around £800. Parts are just over £150 all in so the rest was labour at £65/hr (+VAT).

I changed a front brake calliper last year for about £110 (there’s a £35 surcharge as well) and it took a couple of hours. Depending upon what else has been affected, you may need a new disc as well. That means new pads too. The brake system will need bleeding too. I changed calliper, both discs (one was heat damaged and warped) plus new pads and sensor.

With BMW you might be looking at the wrong side of £1k, a lot less at an Indy.

X5Sport wrote: ↑Fri Apr 17, 2020 7:01 pm I understand your scepticism and after years of having difficult conversations, you are absolutely right to be. Part of the issue is they believe the code reader regardless. Too many BMW (and other) ‘technicians’ cannot work from first principles. Code readers can be wrong although it’s rare as it’s only reading what the car has recorded. I now have an understanding with the Master Tech at my Dealer so we can talk the same language as engineers.

If the dealer was doing the job properly they should clear the code and see if it returns. If it does then it’s real and still current.

You can always say to them that if it doesn’t clear the issue then you ain’t paying!

I didn’t bother servicing the sticky calliper on mine, I just swapped it out.