Some background info: my 2016 Disco Sport has had an ongoing issue of displaying “battery low, please start engine.” Seems like there’s some parasitic drain or some system not completely shutting off.



Beyond that, no performance issues at all. Fast forward to last Friday, I get in, press the start button, dash lights up, gauges go up, nothing happens. It doesn’t provide any error messages, just no crank, no start, no turnover. If I take my foot off of the brake and press the push button just to turn the car on, then I get a laundry list of errors:



- HDC not available

- Gearbox fault

- EBD fault

- Engine temperature indication fails

- ABS fault

- Emergency brake assist not available

- Two wheel drive only, traction reduced

- SOS system not available



Seems like an electrical/computer issue, so I checked the battery first. It’s the original Varta battery, so I assumed it was just shot. I took the battery to AutoZone to see if I could find a stock replacement, and the battery tested good. I put it on slow charge overnight and it holds ~12.75V consistently. I did find that the negative battery terminal was loose, so took the connector off, opened up the gap, and used a lead shim to get it tightened. I took all of the ground straps off of the negative terminal assembly and polished up both ends and the grounding locations on the frame. No change.



Opened up the footwells on passenger and driver side and didn’t find any corroded connectors or wires. Pulled the starter relay and put a jumper across the terminals and the starter engages, so I don’t think it‘s a starter problem. I‘m wondering if it’s the alternator since (even after just charging the battery) I shortly start getting the “low battery, start engine” message.



I’ve seen lots of posts of others having these litany of error messages, but most of the ones I’ve seen, the vehicle still cranks and drives, just no HDC or traction control. Mine does absolutely nothing. I’m pretty competent with mechanical issues, but the electrical stuff is tougher for me to troubleshoot. Any advice that would keep me from having this thing towed to a shop?

 

This same thing happened to my daughters 2019 Sport. Turns out it was a software update that needed to be done. I don't have all the details present as she lives in another state; but I will try to find out what was specifically updated. Hope this helps.

 

Are you using a proper AGM battery charger. 12.75 volts seems low for a Discovery Battery.

 

Did you ever get confirmation that there was a software update required?