spdracer13

I have 2008 RDX and having issues starting up. I though it was the battery at first since it seemed that the vehicle was not getting enough voltage to startup. I changed the battery but the system started back up. I then went to an O'rielly's Auto Parts and had my battery, alternator, and starter checked. The test concluded all 3 parts are good. I place a bluetooth data logger to monitor the control module voltage when the vehicle is on. On my observation, when the vehicle does not have a load (meaning A/C or any other accessory that required a high amperage load) the voltage ranged from 11.9V to 12.6V. On short trips within the city and not turning the AC unit on, when I tried to restart the car it seemed to me the battery did not have enough juice. When I place the AC unit on my voltage ranges from 12.8V to 14.2V. This is what I expect when the car is running. I was looking through several forums but had no luck in finding a fix to my starting issue. Lastly, when the vehicle is on it has no issues, its only when I try to startup the vehicle struggles to startup.

If someone has a resolution or a fix to my issue, I would greatly appreciate any help.

CrAzYNeSs

The starter may still be OKAY but on its way out. I'm the second owner and the only item that had to be replaced in the 9 years was the starter.

Also, instead of using the data logger to log the voltage. Test the battery using a volt meter should be around 12v and check the voltage once you start the car (with alternator charging the battery), should be around ~14v.

This should help you definitely narrow down either the battery, starter, alternator. I'm not sure how O'rielly's performs their tests but the aforementioned is tried and true.

wasup1357

I had similar problems that you did. For some reason it went away after I change out the AC relay. Hope it helps

justnspace

iTrader: (1)

I would do this

littleblazer

Same problem ... Starter....

mrclemson

The first thing you want to do is to measure the voltage on your new battery: assuming it's properly charged, you should see ~12.6V; definitely not 12V when it's charged. Note that a proper voltage doesn't guarantee a good battery but since your battery is new, the voltage does correlate to whether it's fully charged or not.

My intuition is you have something going on with your charging system: because you mentioned that "when the vehicle does not have a load (meaning A/C or any other accessory that required a high amperage load) the voltage ranged from 11.9V to 12.6V" - your alternator doesn't output enough juice so your battery has to compensate for that. You typically need at least 13.5V to properly charge the battery. It's however weird that when the system is on load the voltage shows more "normal" ( 12.8V to 14.2V) - still you shouldn't see a drop as low as 12.8V in any circumstance. Typically when the voltage regulator goes out, the symptom is that the proper voltage can't be maintained under load - I am not sure whether you read it the opposite way, but I would suspect something going on with your alternator.

if you decide to replace it, try NAPA, they carry OEM quality ones made by Denso - which is basically the OEM manufacturer for Acura - at rough 1/3 of the dealership price.

greg1c

The voltage issue is the ELD (Electronic Load Detector), what the ELD does is put the alternator in low mode when there is low AMP draw and in High mode when there was is a high AMP draw. This is normal operation. I would say you have a bad starter.