Fan stays on...Normal?

[nimbus2007]

Hi guys,

is it normal for the fan to stay on for a long time after shutting off the engine? couldn't tell you how long the fan would've stayed on because after 2-3 minutes I re-started and shut off the engine and the fan stopped.

Happened twice already. I'm a little concerned that this has been happening for awhile without us noticing and probably was the cause of our 4 yr old battery draining.

thanks in advance.

[whizmo]

Originally Posted by nimbus2007

is it normal for the fan to stay on for a long time after shutting off the engine? couldn't tell you how long the fan would've stayed on because after 2-3 minutes I re-started and shut off the engine and the fan stopped.

I haven't noted mine being on after shutdown, but I have read that Honda specs that one of the two fans may stay on after shutdown if the engine is unusually hot and may run for up to 30 minutes. Do you note the fans staying on in very hot conditions, being stuck in traffic, or after a long idle period?

It will drain the battery a bit, but if your battery is healthy, it shouldn't be enough to cause a problem.

If your 4-yr old battery is at all suspect, it would be the first thing I'd replace. If the fans seem to be running more often than usual, I'd next suspect one of the two thermostats that controls them - one may be tripping way too soon.

- Mark

[nimbus2007]

thanks Mark. 30 minutes? yikes!!!! well, it wasn't too hot today (high of 60 deg)

also, I replaced the battery (with OEM) last month. I was surprised the original only lasted 4 years and 55k miles and the replacement has a sticker that says 100 months.....

I'll just keep an eye on it

[mobro]

It could be a bad temperature sensor for the fans. I've changed a few on my old 92 Accord. The fans can start after you shut off the engine and temperature starts to increase since coolant is no longer circulating. As soon as you start, the coolant pump starts and the temperature will drop and the fan go off. All guesses on my part based on working on older Hondas.

[pilot_man_dan]

have you checked your coolant level? my fans started running for a few minutes after i shut the engine off, and when i looked under the hood i noticed the overflow bottle was empty. after a little more diagnosis, i discovered my radiator had a pinhole leak, and the low coolant level was what was causing the fans to run.

[nimbus2007]

thanks guys, I will check on both.

[isrb710]

I'm betting it's the coolant level! Mine was staying on longer and longer. The lid to the coolant reservoir tank was not on tight, so I was losing coolant. I had to add about a gallon over 3 or 4 hot/cool cycles. We're now about 5,000 miles down the road and all is well.

[isrb710]

Here's a link to more discussion:

P0128 (cooling system) on 2003 Pilot EX

[nimbus2007]

ok, coolant reservoir was almost empty. got the OEM coolant and filled it up between "MIN" and "MAX" lines. 5 days later and still on the same level, so far so good.

However, the fan still stays on after shut down (longest was 5 minutes), although it was in the upper 60s here the last few days.

I'll keep an eye on it the next couple of weeks and see if it improves.

[isrb710]

Originally Posted by nimbus2007

ok, coolant reservoir was almost empty. got the OEM coolant and filled it up between "MIN" and "MAX" lines. 5 days later and still on the same level, so far so good.

However, the fan still stays on after shut down (longest was 5 minutes), although it was in the upper 60s here the last few days.

I'll keep an eye on it the next couple of weeks and see if it improves.

Check it each day. If you had air in the engine or radiator, it'll take several refills after heating up/cooling down before you get it stable. I think I added 1/2 gallon the first time. Almost a half gallon the next time. Then maybe a pint the third time. I think I filled it all the way to the max line each time.

[nimbus2007]

thanks, isrb710. that was my plan. to keep an eye on it every few days or so....

thanks again

[deanmcneill]

As for the battery, there's a bunch of discussions on battery life on the boards and it seems 3-4 years is pretty much about the limit for the original batteries. I had an '07 and the battery was toast at the 3 year mark and had to be replaced. I've seen posts on this board suggestion that the OEM batteries were somewhat of a weak point in the Pilot's.

[whizmo]

Originally Posted by deanmcneill

As for the battery, there's a bunch of discussions on battery life on the boards and it seems 3-4 years is pretty much about the limit for the original batteries. I had an '07 and the battery was toast at the 3 year mark and had to be replaced. I've seen posts on this board suggestion that the OEM batteries were somewhat of a weak point in the Pilot's.

Lots of opinions here; few hard facts are data. My opinion is that the Pilot OEM battery is more-or-less average and should give more-or-less average life which can be as little as a year or as many as 10+ depending on usage patterns or luck. I think 3-4 years "as a limit" is being way too harsh - I have a six-year old OEM battery in my Pilot that appears to be going strong and many, many others have a similar experience. That being said, nothing wrong with replacing early if you want reduce risk.

- Mark