Did more testing today. I am not able to get it to fail much at all. I did capture one of the events where the current draw in the battery drops to -40A. The battery voltage drops from 14V to 12.5V and the rpm drops. Then the control system bumps the RPM up to 1250. This usually when it triggers the limp mode ect...

I also was able to catch two other problems. Not sure if they are related. When I go for a drive and then stop and put in park the Idle stays at 975. The target on the GAP sensor says 600.
The other issue is sometimes it has a very rough idle.

All three events are shown in the pictures.

 

I don’t know what the GAP tool is measuring for battery amps, but I assume the negative amps means a draw on the battery and positive amps means the battery is charging. While the engine is running, the alternator should be supplying basically all the electricity needed to run the car. I’m thinking your alternator might be cutting out, which gives you that sudden big draw on the battery. If the alternator is cutting out, it’s either the alternator or wiring going bad, or the belt slipping.

Slipping belt can be due to wear, failing tensioner, failing pulley (often idler, but can be any), or something like the ac compressor power steering pump failing and grabbing the belt (or some combination of these problems).

Trying to think if a bad earth strap would cause these kinds of problems, but I’m not sure. I seem to recall that earth strap problems have been noted on the Australian forums as mimicking a bad alternator.

The rough and high idle sounds like a vacuum leak and might not be related. I noticed in your screen shots that you have positive short term fuel trim at low RPMs (lean condition) and this gets better at higher RPMs. That is typical of a vacuum leak, though you really need to look at both long and short term fuel trims (add them together for total fuel trim).

Trying to tie the two things together: valve cover leaks on the passenger side are common - when they get bad enough, you can have a vacuum leak and the oil from the leaking valve cover can drip onto the alternator and make it fail prematurely.

 

On my car, still not much further forward. I did the hard reset and charged the battery and reset the BMS and now when I start it takes about 20 seconds before I have no EBA or HDC or DSC and the suspension lowers a bit but it keeps going and I don't have every other light imaginable. If I stop, restart, all is well again!
Looking at the graphs of the charging and battery voltage I get the impression that the alternator output and load drops and then rebounds and it is at this point that the warning lights come on. Could this be that the battery is a bit duff and the temporary drop of the alternator also drops the voltage and this is enough to disturb things?
Any other ideas?

 

It’s possible the battery is shot, but also possible the alternator is failing or belt slipping, or bad ground. Any of those things can give you a voltage drop. What kind of drop are you seeing?

You should see 14.4v when alternator is going full-on, but the BMS will reduce alternator output when the battery is at full charge (at least that’s my understanding). Even then, I believe the alternator should be putting out enough voltage to power all systems on the car so that the battery stays pretty much fully charged.

If you find a bad battery and replace it, make sure to have the alternator checked as well. Bad alternator can destroy your brand new battery.

Couple of other things that come to mind: (1) brake pedal switch - this failure has been linked to these lights in other posts as I recall; (2) wheel speed sensors - I believe EBA, HDC, and DSC all rely on the abs wheel speed sensing system. There is a wheel speed sensor at each wheel that sits in a bore in wheel hub as I recall. They pick up a magnetic signal from a reluctor ring in the wheel hub. If the sensor or wiring harness, is damaged, or the bore in which it sits becomes clogged with brake dust, it can cause problems. (3) Suspension height sensors - if a height sensor is failing, it might cause the EBA/EDC/DSC to become unavailable.

Finally, here’s a thread where a similar problem was tracked down to a split wire under passenger side door rail. https://www.landroversonly.com/threa...her-one.97546/.

 

I changed the brake pedal switch and the ABS sensors work fine so I can see the wheel speeds with IID. I do have a brake pad wear sensor at the front left which is shot but I am reliably informed it shouldn't affect anything but since this is LR, who knows?

 

Break pad wear sensor won’t affect anything.

 

I'm gonna just throw out the experience I had with mine recently because it sounds similar enough on the off chance it might help. Mine would just completely shut down, like flipping a switch off, usually at a stop light or at low speed thankfully. Then it would fire right back up and go on but have all kinds of crazy error codes come up. Finally stumbled on that both positive and negative battery terminals would not get tight enough no matter how much I tightened them. They would look tight, but could grab them firmly with my hands and they would still twist a little. Sometimes it would just stumble and not completely die.

Negative terminal was worse, so replaced the negative terminal/ground strap ($180 for OEM part ) and surprisingly the brand new one would get no tighter although I did discover that the ground connection on the other end was barely more than finger tight. Replaced the battery as well. Then started experimenting with different methods to shim the posts, like thin metal from the hardware store, lead shim caps from AutoZone...both helped but didn't completely eliminate the problem. Finally tried wrapping some fine copper wire around the terminals with plenty of battery terminal grease and now they are really snug and have had no issues for two months.

Anyway, that was a really long story to say wow these things have very sensitive electrical systems and to check your battery terminals to see if you can budge them when you think they're tight.

 

Battery terminals don’t usually need to be super tight, but ground straps do go bad, both at the body or frame connection point and internally sometimes as I understand it. Definitely something to check here.

 

Rover11 - how do you get the IID graphs as images like you posted? I can export as CSV or PDF only
thanks

 

I'm using an ipad so I just make it full screen and take a screenshot and email it to myself.