Changed Auxiliary Battery, Now What?

Johnnycakes

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Hi

Thanks in advance for the help.

2016 LR4 HSE 47k miles, I am the original owner.

Yearly service and oil
changes.

Tires, brakes at 30k miles.

My ECO start/stop light came on, so I replaced the auxiliary battery with Exide EK151.

Since install, the light has gone off but eco start/stop has not been functioning. I’m guessing this is because I did not use a GAP tool to reset the battery.

I’m also seeing an issue with my dashcam which is connected/powered to my OBD slot. It seems like it won’t stay on/get power when my car is off.

I had my main battery tested at a local autozone and the service clerk said it was still good.

anything else I can do?

Thanks
 

hickersb

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If your main battery is weak (the system thinks its not strong or sufficiently charged enough to reliably start the car), the ECO start / stop light will be off but the start/stop function won't work either. I'd do the battery reset (for the aux battery), and see if starts working. If not, I'd check main battery voltage.
 
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ftillier

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If you want constant 12V battery power, unswitched, pin 4 on the trailer brake module plug under the dash is wired straight to the battery with a 30A fuse. You should make sure to have a low-voltage cut-out so you don't drain the main battery to the point where you can't start the engine. The 2011 wiring diagram identifies it as a pink and white wire, and should be the thickest wire in the plug.
 

callin

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My ECO start/stop light came on, so I replaced the auxiliary battery with Exide EK151.

Since install, the light has gone off but eco start/stop has not been functioning. I’m guessing this is because I did not use a GAP tool to reset the battery.

I’m also seeing an issue with my dashcam which is connected/powered to my OBD slot. It seems like it won’t stay on/get power when my car is off.

I had my main battery tested at a local autozone and the service clerk said it was still good.

anything else I can do?

Thanks
Same thing happend to me - I replaced my Stop/Start battery and the light has never come on and the stop/start no longer functions. I called it a win/win!
 

djkaosone

'11 LR4 HSE LUX 5.0L V8
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Would be pretty cool if you stuffed a 100Ah Lithium battery under there for all your accessories, if the start/stop eco doesn't work.
 

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