Dear Scotty,
Our 2005 Honda Pilot, 225,000 miles, has a new electrical problem. It occasionally will not crank over/start after sitting overnight.
The battery and starter are approximately 5 years old and are name brands such as Nippondenso.
I have had the battery, alternator, and starter checked out. The battery and starter checked out ‘okay’ while the alternator checked out as ‘weak’. I put in a new $300 alternator and it does seem to run better when major electrical loads turn on such as the AC clutch.
However, just this morning the car would not start. What are typical parasitic loads that could be causing trouble after the ignition is turned off?
Any ideas on where to look?
Thanks in advance,
Pete ‘The Missing Link’
See Scotty's video on parasitic drains. Load test the alternator and battery even though they are "new."
The battery and starter are approximately 5 years old
A 5-year-old battery is highly suspect. In fact I recently replaced a 4-year-old one to fix the same symptom. (Depending on the equipment used and actual internal condition a battery test may not be entirely accurate.)
What are typical parasitic loads that could be causing trouble after the ignition is turned off?
https://www.youtube.com/watch?v=KF1gijj03_0
I hesitate on the battery replacement after buying a battery for my kids truck at $250, especially after the $300 alternator.
Checking online it looks like the OEM battery for your Honda is a group 24F. That is one of the most common types around, with wide availability.
You should be able to buy a perfectly good battery from WalMart for about $150. They actually have group 24F batteries as low as $60 but those are lower capacity, 550 CCA I think, probably not a good choice on a modern car. However it does look like the original battery is Honda 31500-SD4-100M, rated at 550 CCA. (More is better though, especially if you live in an area with cold weather.)
https://www.hondapartsnow.com/genuine/honda~battery~assy~31500-sd4-100m.html
(Disclaimer: This info is all obtained via internet searches.)
A battery might be even less at Costco if you're a member. Chances are that even if there is some other problem your battery is not going to last a whole lot longer.
I am planning to use an ammeter in the negative battery cable.
That should tell you whether you have a parasitic drain problem. You will likely find that when you connect the ammeter there will be an initial surge while the modules initialize which will subside to milliamps when they "realize" the car is turned off and modules go into sleep mode and any energized relays are turned off.
There is probably a specification for your vehicle but the general rule of thumb is it should around 25-50 milliamps with the ignition turned off.
Checking the current draw it is at 0.150A with the ignition off. That seems high. Given it is a 2005, it is pretty old and I would guess the 0.030A target for ECM current draw is probably closer to correct. Off we go to pull fuses.
Pulled all the fuses and did not change the current draw. Crawling under the dash I found the old 'Crime Stopper' remote start system I had installed 11 yrs ago as a gift to the wife. Unplugged the 'DBALL' CAN bus adapter and current draw went to 0.03A. CAN adapter and Crime Stopper Cool Start RS4-G4 box are now removed. I hope everything else still works! That remote start was a piece of junk anyways. Stopped working a few years ago. I cannot believe I paid someone to hack it into the car - I mean professionally install it. The things we do for love, eh?
Hopefully I am close to the end on this.
After watching the parasitic load test from Scotty, I found it was similar to what I was planning to do but was hoping to avoid since intermittent electrical problems are hit-or-miss. I say similar because I am planning to use an ammeter in the negative battery cable.
Are there typical Honda Pilot problems like this that could give me a head start on the troubleshooting?
I hesitate on the battery replacement after buying a battery for my kids truck at $250, especially after the $300 alternator.
Hopefully I am close to the end on this.
150mA is a bit high, but shouldn't kill the battery overnight. It wouldn't hurt to get it thoroughly tested at Autozone or a battery dealer. The years of parasitic discharge may have degraded it.
Battery still checks out OK. Was just at the parts store - while checking fuses, one of the 40A fuses went flying and I could not find it.
We'll have to give it the 'test of time' over the next couple days and see how things go. It appears that after removing the remote system, everything still works.