Hello,

I have a 2016 Jaguar F-Type R Convertible and I’m experiencing persistent battery charging/draining issues, possibly related to the BMS.

What Happened:

• Installed a new exhaust system, which triggered a check engine light.
• Connected an OBD II scanner — showed an O2 sensor fault (probably caused by a small exhaust leak).
• Fixed the leak and cleared the code.
• Drove the car for about 2 hours with no issues.
• After sitting for 3 days, the battery was completely drained (4.5V).

What I’ve Done Since:

• Installed a new battery, but immediately received a “Charging System Fault” message.
• Tested the alternator (13.7V at the battery while running; passed load test).
• Noticed and replaced a broken battery sensor connection at the negative terminal (no change).
• Fully charged the battery and let it sit 16 hours; voltage dropped to 12.0V (~40%), confirming parasitic drain
• Noticed a clicking module in the trunk near the battery that clicks about every 20 seconds and continues hours after the car is off.
• 
• Reinstalled the battery and checked all connections again (no change).

It appears the clicking module in the trunk (BMS?) never goes to sleep and is slowly draining the battery. I’ve read that OBD II scanners can sometimes interfere with vehicle modules and electronics, which makes sense since this all started after I cleared the error code. I also did not register the new battery, although I’ve replaced one before without registering it and had no issues.

Has anyone experienced something similar? What’s the correct fix or diagnostic path? Video of the "clicking" attached.

Many thanks in advance!

 

Was the new battery registered via the code reader?

EDIT: Here is a video of an example of someone doing this. This will vary based on reader/software you use to do this... but just so you get the idea:

 

Sorry, I re-read your post. You did not registered the new battery. That could be the issue now, even if you got away without doing so in the past.

 

Close and lock the doors. Come back in half an hour. Is the red triangle on the dash still lit up? If so, that’s your drain caused by OBD port shenanigans. Should clear by disconnecting the battery ground for a few minutes and hooking it back up.

Did you test the old battery or the new one with a good tester that has an AGM mode?

Supposedly you don’t have to register the new battery with the BMS but if that were true why does Autel allow you to register the new battery? Better safe than sorry.

 

Yes, the red triangle is still up. I did disconnect the battery ground for several min and it didn't change anything.

Both new and old battery were tested with an AGM charger. The first one was dead, the second one got depleted pretty badly but I could eventually revive it.

Is there a way to reboot the BMS by itself?

 

That would definitely be a relief if it’s just that. Hopefully it’s not too late.

I’ve ordered a new scanner that can register the battery on the F-Type. I’ll update you once it arrives.

 

If the red triangle is still on then the car is not at its lowest power state. That’s the draw. No idea why it’s still awake after a power reset (battery disconnect).
That’s all i know for sure.

 

Yes. That's the classic battery drain issue on 2016/17 era cars when an OBD device is connected

Disconnect the battery. Maybe give it a few minutes. Reconnect it. (Don't close trunk with battery disconnected!)
That should fix it. Nothing to do with BMS. And no need to reset BMS or anything else in my experience
It's a known issue with a module not shutting down if the OBD is disconnected without the proper handshake

Try again battery disconnect and see if that fixes it.

 

For sure, don't close the trunk with the battery disconnected! I throw a blanket over lip to cover the latch to remind me not to close it when disconnected.

 

Not only specific to the older models. Mine had that and it was new of the showroom floor (a 2024 bought new a few weeks ago). I had to disconnect the battery to get it fixed.

But OP mentioned doing that already and not working. Reason why I suggested fully charging the battery and then registering it with a code reader.

 

Right, I tried the battery disconnect already, twice. Doesn't work. Still awaiting my scanner tool from Amazon to register the battery and reset the BMS.

 

I have a vague memory of someone here with this issue, car wouldn’t sleep even after a hard reset. I think the QCCM (Quiescent Current Control Module) is what’s supposed to put the car to sleep. Whether that person had to replace the QCCM or if there was some other solution, I don’t recall.

 

Update: I reset the BMS and registered the battery. No change. The hazard light is still on (30 minutes after shutdown), the clicking near the battery continues, and the battery is still draining.

However, looks like DJS is on to something:

I just ran a deeper diagnostic and guess what I found as permanent error code... B1412-87 - Quiescent Relay Box (under Gateway module).



From what I understand, the “-87” usually means a missing message, so the Gateway isn’t properly communicating with the Quiescent Relay Box. That would make a lot of sense. It’s probably why I’m hearing the clicking sound, why the car never fully goes to sleep, and why the battery keeps draining. This really feels like the root cause!

Question is now whether I have to replace that part, and if so, if I can do this myself or if I need specialist software to register/connect it properly.

Please let me know your thoughts (or if you could find this other post).

 

B1412-87 equates to "Quiescent Relay Box - Missing message" and the diagnostic procedure is "Refer to the electrical circuit diagrams and check the LIN bus circuit (LIN 1) for short circuit to ground, short circuit to power, open circuit, high resistance. Repair the wiring harness as necessary". While it's possible the box is defective, you mention finding and fixing a damaged battery sensor connection in your original post. It turns out that sensor also uses LIN 1 for communication so I suspect your issue is either a harness problem (short to ground, broken wire, etc.) or the battery sensor is damaged. You might want to try unplugging the battery sensor and seeing if that changes the relay box behavior.

 

I’m afraid I don’t understand most of what you wrote about the circuits or what the “wiring harness” refers to. If I send a photo, could you point out which cables I should check, and how to best check them other than just visual inspection (e.g. multimeter etc.)? Visually, it all looks fine to me.

For context: the previously broken battery sensor is circled in red in the photo (that’s where the sensor cable plugs in). I replaced the entire part and plugged the original cable back in. As far as I know, the cable itself wasn’t damaged, and the connector on the cable end looked fine.



What I still don't understand is this constant clicking. It's not coming from the Quiescent Relay Box, but from the box to the left of the battery. Can anyone confirm what that thing actually is?

 

The previously broken battery sensor (BMS) is your clue. The piece you circled connects to the semi-circular device that is the source of clicking. You will need to pull up the panels on top of the battery to trace those wires. There may be a short somewhere along there. Also check the termination of the negative ground cable from the battery to the metal of the trunk - it is somewhere near there under the carpet. If anything is loose that could cause your symptoms.

 

A LIN (Local Interconnect Network) Bus is a three-wire network (12V power, ground, and data) controlled by a single master device (usually the body control module -- BCM) and a number of non-critical slave devices (such as the battery monitoring sensor, door locks, window switches, etc.). The error message is indicating that there's something wrong with the LIN 1 network at the Quiescent Relay Box. In a LIN Bus, all of the devices share a common data wire (which in your car is a white wire) so it's very possible the battery sensor is the problem and taking down the network -- either there's a broken wire, a shorted wire, or an internal short in the sensor itself. If you bought a cheap replacement sensor off Amazon or EBay instead of a genuine OEM part, it could be bad from the start which is why I said to unplug it and see if the relay clicking noise goes away. You're usually better off with a genuine used part than a new, bargain priced "made in China" part when dealing with electronics and sensors. If you can't find a wiring problem you may need to bring the car to a specialist -- someone with access to wiring diagrams and an oscilloscope to do a proper diagnosis. Other than checking power and grounds, there's really not much you can do with a multimeter.

 

Thanks, that's very helpful. I just disconnected the cable, and the clicking stopped, but started again right after putting it back. The negative terminal seems properly grounded.

I don't see anything loose, but as you can see on the attached video it's pretty hard to follow the cable. I’d be surprised if the cable is the issue since only the connector on the negative battery terminal broke off. The cable and its connections were never damaged. Also, I can't say for sure when the connector piece got damaged, and it's very likely that this was damaged after I got the error message on the dash (while replacing the battery).

Correct me if I'm wrong, but looks like there are two remaining suspects:
1. The BMS module itself is faulty: The new sensor is sending correct data but the BMS is misinterpreting it or has corrupted firmware. The BMS needs either reflashing or physical replacement.
2. The QCCM is faulty independently: Separate from the BMS issue, the QCCM relay is stuck closed.

Which one is more likely? Or it's both? The BMS is faulty and causing the clicking, AND the QCCM is stuck causing permanent power to cabin electronics?

Is there a way I can diagnose this properly without replacing these parts?

 

Yes I got a cheap replacement on Ebay. It stops clicking when I unplug it. Does that mean it's working?When you say the error indicates an issue with the LIN 1 network at the Quiescent Relay Box, are you referring to a specific cable going into that box? I’m confused which wiring you mean. The cable on the negative battery terminal comes from the BMS, so I want to make sure I’m checking the right thing.

Please take a look at the video I uploaded earlier and let me know exactly which cable or connector I should inspect. There are many wires there. Are you referring to wiring at the Quiescent Relay Box, or at the BMS?

 

No, that does not mean it's working -- it means your cheap Ebay replacement part may be the problem. Unplug it, clear the codes, and then rescan to see if you still get the same B1412-87 error. If it goes away, buy a genuine part (C2Z16597) or get a used one from a salvage yard. Every Jaguar model since 2013 has been using that same part so it doesn't have to come from an F-Type. In fact, it's probably used in every Land Rover model since 2013 as well.

What I was trying to convey earlier is that EVERY component on the LIN 1 bus is connected to the SAME white wire for transmitting data . You can see it on the video you posted of the battery connector. You'll also find that white wire going to the Quiescent Relay Box, the body control module, and every other devices on the LIN 1 bus. That's the wire you need to scrutinize first if the Ebay part isn't the problem.