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Yesterday, I used the RDX and I had no problems starting. Today, I went to start it and all it did was "chatter" and the dashboard lit up. The only way that I could stop the chatter and get all the lights on the dashboard to stop, was to push the start button two times. Does anyone know what is going on?
I just tried again and on the dash it showed "Accessory Mode". I tried a few more times and now it is completely dead. I could not even lock the car with the remote. My friend checked the terminals on the battery, and they are not loose. The battery was replaced in January, but that does not mean that it has not discharged. I only use the car every few weeks, so that might indicate the battery is dead. However, I would not think that a new battery would discharge like this. If it is the battery, any idea what would be draining it? When my neighbor comes home from work, I will ask him to jump it.
Sometimes the HFL module (Hands Free Link) goes bad and drains the battery. If you have any aftermarket accessories installed (dashcam, amp, phone dock, etc), could be one of those. Make sure all your interior lights are switched off or to door mode only. It's not fun troubleshooting ghost current drain.
I have a Base RDX and I do not have any aftermarket accessories installed. I do remember connecting the Bluetooth on my phone to talk hands free the last time that I used the car, but I know that I turned off the Bluetooth on my phone. Is there any way to turn on/off the Hands Free Link from the car? If I get it started, I will need to make certain that I am not leaving anything on in the car.
I only use the car every few weeks, so that might indicate the battery is dead. However, I would not think that a new battery would discharge like this.
I still have the original battery in my 2017 RDX which means it is now 6 years old and going into its 7th year.
I had my car stored for three months without a battery charger/matininer connected to it and I was amazed that it started as if it had run the day before.
So if you have a good battery and the charging system works, you should not have any trouble.
You should invest in a DMM and a load tester, both available from Harbor Freight. Also check your cables for corrosion at both ends.
And you might get one of these on Amazon that you can plug into your cigarette lighter. When the engine is running, you should see 14.0 to 14.4V.
In retrospect, I probably did not need to replace the battery in January. I think the problem at that time was a loose cable connection. But I wrongly thought that the battery was coming to an end, so went to Costco and bought an Interstate Battery. If the car starts with a jump, the nice think about Costco is, I can get the battery replaced.
I had AAA jump the car and check the electrical system. They said that the battery should have 12.66 volts but it was showing 7.6 volts before the jump. I believe that it was also showing 7.6 volts after the jump. The alternator checked fine and they could not find anything obvious that would be draining the battery. I would not expect them to be able to find a problem with the HFL module. I found my receipt and the battery was replaced at the end of December. Certainly, I would not expect a battery to go bad in 4 months, but I also would not expect that the battery was bad when it was first put in. I guess that all I can do at this point is return the battery to Costco, buy a new one, and see what happens.
I guess that all I can do at this point is return the battery to Costco, buy a new one, and see what happens.
Well that is called "guessing" as to what the problem is.
Even when I was not an electronics technologist, I still owned a voltmeter or now a DMM, Digital Multi-Meter. About $25 buys you one and always look for one with a 10A DC amp setting. At least you can do some basic checks with that option.
This one is Auto-Ranging and best for those not that clued in with electronics. It does not have an AMPS option...no big deal if all you want to do is measure volts.
Thank you and I will get one from Amazon. Would you expect it to show 7.6 volts on the battery as tested by AAA?
If you saw 7.6V with the engine off, you either have a dudd battery, a load (accessory) that is draining the battery when parked or an alternator that is not doing what it should be doing.
Engine off with no load on the battery, not even a dome light: 12.6V - 12.9V depending on the battery type.
With the engine running: 14.0V - 14.4V. Charge voltages are temperature dependent and also based on battery type. I have seen 15.0V in my car that has an AGM battery and 40°F ambient temperature which is perfectly normal.
I got your PM, but I'll answer your questions here for others to see if they have similar issues, etc.
As the AAA driver said you might have a bad cell. At 7.6V, probably more than one bad cell or a discharged battery as well as maybe a bad or more bad cells. Kind of rare on a new battery, but possible.
As for your other questions, the cigarette lighter outlet is inactive when the vehicle is OFF, so you cannot get a reading of the battery voltage as shown below. If you want a voltage reading of the battery (Accessory Mode and Engine OFF) you will need to take it at the battery itself using a Digital-Multi-Meter.
You can get a battery reading when in the Accessory Mode with the Engine is OFF. The voltage will always be lower than the Open Circuit battery voltage (battery not connected to anything) and is based on what systems are on in your car. More systems or mode load, voltage decreases. I am sitting at 12.1V which is a tad low, but then I have no idea what systems are on in Accessory Mode, yet my cars starts as it did back in 2017 when I bought it new, so I am not concerned.
Battery reading with the Engine ON at idle. It is always at 14.4V.
If you are confused about using DMM, there are plenty of YouTube videos providing very simple instructions.
This basic video does a reasonably good job of it. BTW, I happen to have that exact yellow DMM that I bought at Walmart. Although I have an expensive Fluke 88V, that Innova 3300 is all you need.
Unfortunately, I am now questioning if the AAA person took the 7.6 volt reading with the car on or off. He did take the reading on the terminals of the battery. There is no question that the battery was discharged, I do know that he said that the battery is bad (hopefully he is correct), and he said that he can't detect anything wrong with the electrical system. The battery is now out of the car, and I will exchange it at Costco this weekend.
I will order the cigarette lighter voltmeter and Digital-Multi-Meter. For my purposes, do both the cigarette lighter voltmeter and Digital-Multi-Meter take a volt reading; one from the cigarette lighter and the other at the terminals of the battery?
For my purposes, do both the cigarette lighter voltmeter and Digital-Multi-Meter take a volt reading; one from the cigarette lighter and the other at the terminals of the battery?
No, I do not have a battery charger. Only AAA and Costco's return policy
You might consider getting a Pro-Logix PL-2320 Charger/Maintainer. Recommended by my co-workers after I retired from the labs where I worked. Lots of YouTube videos reviewing it. I got mine at Amazon.
Originally Posted by Anovice
How will I go about testing the HFL module to see if it is draining the battery?
Although someone told me before, I have no idea what a HFL module is. Damn acronyms and I would know, Porsche has countless acronyms.
The following video is excellent in finding parasitic drains and shows some of the errors people can make. I viewed it a couple of years ago and it is a bit long (38 minutes) but well worth watching. Gone are the days of simply disconnecting your battery to place a meter in series and to pull fuses. That worked before we went to CANBUS systems. Note during the first part, he is shutting the vehicle down as if it is "parked" and that is important.
Tech, thanks for your post. I will review the videos tonight.
Talking about acronyms and language, "car people" have their own dialect and viewpoints. While I very much appreciate your suggestion, I say to myself why in the world would I want to charge a battery. I know that my alternator is working (AAA), that's what the car should be doing, and if it is not, then the car has another problem. None of this diminishes my appreciation for your suggestion!
By the way, in the second video above, the presenter makes a mistake at the 7:02 mark. 1006 milliamps is 1.006 A and not "about 0.1 amps" as he mentions.
Originally Posted by Anovice
Talking about acronyms and language, "car people" have their own dialect and viewpoints.
Coming from aviation as a flight instructor before going into electronics, I can tell you all about acronyms.
Originally Posted by Anovice
While I very much appreciate your suggestion, I say to myself why in the world would I want to charge a battery.
I have a slew of charger/maintainers because some of my vehicles (4) are stored for the winter. A fully charged battery is one with a long battery life and I know something about a long battery life.
Plus that Pro-Logic has a 20A Power Supply mode as well to supply a vehicle while I am working on it. And when doing tests, batteries should be fully charged.
Anyway, good luck and let us all know what the issue is.
05-01-2023, 01:09 PM
