I've been travelling a lot lately and have put very few miles on the RL. Yesterday, after sitting in the garage for a week, I took it out and immediately, the CMBS and ACC warning lights turn on and stay on.

I was heading near the dealer so I called and stopped by. About an hour later, I'm out with a new battery (after almost 4 years, 50,000 miles, and a larger bill than a battery is really worth) and all is well again. The old (original) battery tested at 306 CCA and 11.85 volts (should be 550/12).

It's amazing how many little gremlins show up when the battery gets weak.

LL

 

I somehow don't see the connection between weak battery and CMBS/ACC. Maybe all it needed was a reset?

 

I am having the same issue. The light has come on all of a sudden and it wont go off. I've only had that happen when there is snow on the radar infront and the car cannot see.
are there instructions to reset it?

since I'm just out of warranty, I am sure Acura will want to charge me an arm and a leg to fix anything.

 

have you tried cleaning the front plastic over the sensor or pulling the battery terminals? it's a bit n00b but it just might work...

 

I have tried the plastic cover cleaning, but did not try the battery. is that the best way to reboot the RL's computer?

I would have expected some key combination to reset the computer from inside the car. Been reading too many horror stories of people having to pay money just to get the computer reset since it went haywire.

My brake pads were low on the front tires and I thought it may have to do with that, but I just replaced them and still getting the same thing.

Also, is there anyway this could be related to the master brake cylinder recall? I red in there that you should take your car in if any of the system lights come on.

 

This was actually the second time I got the CMBS/ACC warning lights. The first time was the day I bought the car, as I left the dealership. Something went wrong and they had to replace a lot of parts and recalibrate the system. Yes, it would have been very expensive outside of warranty. This time, the new battery solved the problem. If your sensor is clean and a car reboot doesn't work, get your battery tested. Unfortunately, this is something you probably can't go to an independent repair shop for since the recalibration requires some specialized equipment.

LL

 

Thanks. I just replaced the battery a year or two ago, so I doubt I can get away with it that easily.

reconnecting the battery did not help either unfortunately, so I will have to take it in and see what is wrong.

 

I took the car in today and paid $150 for them to look at it. In the end they could not figure out anything was wrong and just ended rebooting/resetting the system.

This should be something customers can try before having to pay to have it done.