LokiRN

Hello,

2007 tech, new battery early 2019, alternator early 2020, starter late 2020. Been fine till now.

Past week been having sluggish hesitant starts. Starts within 3-4 seconds. Not as crisp as usual.
My check- Battery terminals read12.6v, drops into the 8v range when starting. Engine running Batt= 13.9v
Lights fine, no dimming or brightening with engine running/ revving. Lights do dim at start. No warning lights.

When arriving yesterday home after 35 minute drive the RDX will not restart. Batt=12.6v and drops into 7v range when trying to start. Starter clicks.
Let it rest about ten minutes and it starts again. Starting voltage back around 8.7v
Battery check at NAPA next day- they said Batt was fine with CA=819 and passed test for batt rated CCA 640. This was after only a 5 minute drive to NAPA. RDX then started with same sluggish start.
Today after 40 minute drive home- again no restart with same battery readings. Restarts after 10 minutes.

I plan to stop by for a battery/ charging check on way home tomorrow to see if that changes anything.
I won't have time to check the RDX out till this weekend. Anyone else had a similar issue?
Thanks in advance for any info,
Regards,

Tomtwtwtw

Early 2019? If I get 3 years out of a battery I'm buying a lottery ticket. 2 years is pretty normal for me, maybe 2.5 if I get a good one. Definitely swap that battery out and see if the symptoms persist.

LokiRN

Thank you Tomtwtwtw
Yep, I am highly suspicious of the battery especially with that voltage drop when starting.
Hadn’t heard of a battery going weak and then recovering a few minutes later.
I expected NAPA to confirm bad battery but that didn’t happen.

As you say, battery is about due so I’ll probably replace it even if the battery/ charging test today can’t pinpoint the problem.
After that I’ll take it to a shop if I can’t think of something else to troubleshoot

Regards,

deepa1600

Mine had same issue, in cold weather had hard time turning over. One time i drove for 2 hours and went inside costco after 10 min i came out and it didn't start. Waited for 10 min and then started right up. So i changed the starter with a reman unit from amazon and haven't had single issue after that. I also changed all 3 ground cables in engine bay as corroded cables can also cause these issues. In my case it was a starter though.

Tomtwtwtw

As Deepa mentioned above, next steps I think would be to look at wiring, assuming a new battery doesn't fix the issue. Corroded wiring can cause issues when you try to pass a strong current through them. I did have to replace my entire positive terminal a few years back due to a corrosion issue that eventually started causing the car to randomly shut off because it couldn't maintain the connection.

LokiRN

So, arriving at Autozone I asked for battery and charging test. Only had battery check done at NAPA.
Battery good, Starter bad. This reading was when the RDX would not start.
They got busy and I couldn't wait for a retest with a vehicle that would start.
Out of curiosity I will get another test done when the RDX will start in order to compare results.
Time to check some starter cables, ground cables, youtube videos and parts availability.

Thanks for the replies Tomtwtwtw and Deepa1600

deepa1600

In my opinion it's a tiny starter with no visible solenoid. Usually starters have a large solenoid on the outside but in RDX there is no no visible solenoid at least not on the outside. I am pretty sure you need a starter.

LokiRN

Stopped in to Autozone for another system check and waited till car should start.
Battery good
Starter failed on both crank speed and current draw.
Looks like I have plans for Friday.

Thanks for the info.

thoiboi

Where did you buy the last starter? I would try to get a new/reman'd DENSO in your shoes. This looks to be the one for a 2007 RDX: https://www.rockauto.com/en/moreinfo...LPKiWDWhPompQq

LokiRN

Thank you thoiboi.

Back then I had the RDX towed to and starter replaced at Honda dealership. I believe a Remy was used- Denso not quickly available.
I contacted them and they will replace under warranty if defective so I just dropped it off today.
My only concern is if the positive battery cable has issue to the starter and I did not check that. I think high current draw and low crank rpm could be caused by a bad cable or connection.
Anyway, I will update finding on Monday. If any warranty issues w Honda I will do it myself.

Regards,

LokiRN

Starter was the culprit- you called it Deepa1600. Replaced under warranty. Cables are fine.
Honda dealer said battery is weak now and needs to be replaced. Not done. Its an AAA battery still under full replacement warranty if I find it to be bad.
RDX cranked instantly when I picked it up this evening.

Thank you guys for the quick replies,
All done here!

bendavid

Thanks, I have the same problem suspected it was the starter