So my battery is flat. Trying to charge it from the front but not going well. Sounds like I need to remove the battery and have it tested or replace it. I can start the car now as it will not recognize my key. Even if put down by the sensor on the left. Remotes will not work to pop the boot nor will the button on the rear hatch. What is the trick?

 

If your battery is discharged too far a smart trickle charger or maintainer won't be able to recharge it because they battery voltage is too low - it either won't start to charge or take forever. Use a standard type dumb charger to charge it for 5 - 8 hours and you might have some luck unless the battery is indeed internally shorted or has a bad cell.

 

You need to use a battery charger on the engine compartment terminals. As previous, a trickle battery maintainer will not do the job.
Perhaps you need a new battery but with a long duration charge at high enough amps you will likely get enough juice into the battery to activate things.
Buying a decent full power charger is much cheaper and less likely to damage the car than a tow job!!

I use a CTEK on the front terminals and it works just fine as a maintainer.

 

Something doesn't make sense or at least hasn't been fully explained.
How did you open a door to pop the hood if you don't even have enough battery power to pop the hatch?
Did you use the emergency key in the fob to open a door?
Usually when folks have a flat battery and can't open the hatch to access the battery they use that key to open a door then pop the hood then use a trickle charger/battery maintainer on the engine bay connections to get enough power into the battery to at least pop the hatch.

 

If you have another vehicle that you can hook up, at least briefly, to the terminals under the hood, you should get enough juice in the system for the button on the dash to pop the hatch even if it isn't enough to crank the engine. Been there, done that due to the dreaded OBD port drain at annual inspection time...

Leave your remote out of the opening process if you can help it.

 

I had to hit the unlock button on the remote to stop the alarm when power was applied to the underhood terminals, when I suffered a flat battery.

 

Got the boot open and got the battery charged to 96%. Load test it today to see if it is any good before re-installing the boot battery.

 

Now I am pleased that my convertible has a manual trunk latch mechanism!!
Thought it was a bit cheap at first!
Though, on second thoughts, I am not sure whether the manual release button will operate the trunk release without power
I guess I will trust the CTEK!!

 

[QUOTE=CJSJAG;2361521
Though, on second thoughts, I am not sure whether the manual release button will operate the trunk release without power[/QUOTE]

You can be sure it won't open without power.

 

So read today why my battery was dead. Had a DMV smog test done 2 days earlier. Car was not going to sleep.

 

How does the CA smog test interact with the car?
In MA they only appear to put a probe in the exhaust.
Does not seem like any electrical/electronic interface.

 

OBD2 Plug IN is what they do for smog in AZ. I read threads that anytime you plug into it under the dash you need to do a battery Neg cable disconnect to reset the systems. Systems does not go to sleep and drains down pretty quickly according to other posts.

 

Not entirely true. Some OBD devices cause the problems, but not all. I've had dealers and independents plug into my OBD and never had the problem. Others have not been so lucky. The trick is to check the light in the hazard switch - if it hasn't gone out within about 10 minutes of locking the car, you're in trouble.

 

Light was on and I thought it was odd but new car. The other odd thing is that before the Illuminated sill plates were not working. Now they are so maybe and issue was going on. I am going to have the battery loaded tested this morning before installing. If bad they have them for $200.

 

As I recall from some of the threads, it seemed that they need to let the program run all the way through to conclusion before unplugging. I made that reminder at my last inspection and did not have the discharge issue...could be coincidence, could be updates to the Texas inspection program, or perhaps it was that they listened to me. Regardless...I was much happier in the days that followed...

 

Battery load tested fine. Install was like 10 minutes. Fired up just fine. Detailed under the bonnet while doing the final charge to 100%. Sill plates now working too.

 

You will learn from bitter experience to carry a small adjustable wrench at all times.

It fixes all sorts of electrical issues....just pop your trunk, remove the +ve terminal for 10-30 seconds or even longer if you feel inclined, and bingo, everything is back to 'normal'. You will most probably have to reset your window roll up/dn function and the centre display, but that's it.

 

CA smog did the same thing to my car. Although I had anticipated it.

 

In MA they have to plug into the OBD port as well, so you could definitely see this issue after a MA inspection.

 

Agreed. They plug into OBD in MA state inspection. And it triggers the battery drain issue on my 2017 SVR. Have to unplug the battery else it's dead within a couple of days. Even on the ctek.