Slight Burning Smell + 1/2 lights on dash light up?

I have a 2002 Honda Odyssey. The other day while driving, and today after just starting up, the car makes a whining noise, multiple lights on the dash illuminate (charge, all door open indicators, brake, and brake light bulb indicator) and when I open the hood I can smell a slight burning smell.

I thought maybe something was frozen, but the belt is not unusually warm, and all the pulleys I can see are turning.

Any thoughts?


Your alternator is more than likely seizing up… Have an assistant start the car while you look under the hood… Be ready to tell him to shut the engine down after you confirm the alt pulley is at a standstill… I bet you find that your alternator has bit the dust… Not a major issue…just replace the Alternator and install a new serp belt…and you will be good to go.

Its almost a textbook Alternator Seizure…the lights on the dash are further clues to this.


Thanks Blackbird. I can’t complain – 185,000 miles on an alternator is pretty good!
– Chuck

Surely is…bearings dont last forever… Can you imaging how many revolutions that thing has made over that many miles? Esp since it turns at like 2 to 3x the speed of the engine? DOesnt owe you a damn thing… And it still works probably…just the bearings failed…

Interesting. I changed the alternator yesterday, and had the “new” one bench tested before leaving the auto parts store. Car ran fine. Then today, on my way home from dropping my daughter at the airport, the same symptoms appeared while driving down my street – they lasted for about 5 seconds…

Does the drive belt run other things, too (and maybe an idler puley)? If some other pulley is dragging, maybe it’s slowing (and burning) the belt and reducing the output of the alternator.

hmmmm. This belt also runs the A/C (which I haven’t used in 3 years because it tore itself apart from the inside out and I don’t want to pay $2,000 to replace the entire system (i.e. to remove all the aluminum shards)), and the idler/tension pulley. When I had the “old” alternator on the tester, even though the tester indicated a bad diode, the output was still slightly above 14volts…

Yes the belt should run several things esp if it is a serpentine belt…which runs everything…

Oh my…Didnt you check the OLD alternator shaft after you had the belt off? If it spun freely then that wasnt it… Might not have been the alternator seizing…could be another culprit driven by the same belt… Didnt you check the alternator shaft on the OLD alternator before changing it to confirm? Was it seized, trouble moving? Prob not… Something in the system is either seized or seizes up when running…when it does…it prob stops the belt…which set off the warning lights on the charging system…bec the alternator gets slowed enuf or stopped whenever the mystery part seizes up. I think the odyssey has a single belt…I’d have to check… But something along that belt is having issues… could be a tensioner, idler pulley, PS pump…hell anything on that system…

I SINCERELY apologize I should have said to remove the belt and see/confirm what is able to spin free and what does’nt spin free or well…The alt is definitely one item that it could have been…The alt was affected…but… This is a check that I would have done this without thinking much about it, just to confirm what the seizing item was…and I guess I also didnt write it down for you…I’m so sorry that I didnt write it down for you…Its just such a natural thing to do…check which item was seizing while the belt is off… I should have told you this instead of blaming the alternator right off the bat… The alt apparently got slowed or stopped when whatever other device got locked up… My SINCERE apologies…Now I feel bad

Well, here’s what I do know:

  1. The alternator tested with a bad diode anyway, so even though it wasn’t seized (yes, I was able to spin it), that diode could not have been a good thing – so that’s that. New alternator bench tested fine.

  2. There are only two other pulleys using this belt (in addition to the main shaft from the engine) – idler/tension and the A/C Compressor.

  3. The problem at this point is very sporadic – it would have to be occurring when the car was in the driveway for me to shut it off and check it out. When it’s not happening, everything appears to be “normal”.

  4. I might try to see if I can reach the idler pulley to relieve tension from the top-side rather than having to remove all the plastic coverings from underneath the car to reach it. Then if I remove the belt, I might be able to determine what’s not rotating freely.

  5. On second thought, though, with the A/C Compressor being at the bottom of the compartment, I may not be able to get to it to rotate it from above.

  6. From what I can tell, nothing is locking up – but that doesn’t mean everything is freely spinning…

  7. There is a second belt which solely operates the power steering pump…

It looks like there are 2 engines possible on this vehicle… One has a single serpentine belt which drives EVERYTHING…did you do this work yourself? Or did someone else do the work for you? I guess I am getting confused as to how you may have missed the big clues…sorry.

THE OTHER engine has two belts…a PS belt and a serpentine for everything else. WHen the belt was off a cursory inspection of all the driven components should have been first and foremost just to see whats what…and to test the Alternator theory… Something in this system is obviously having trouble rotating…it should be very easy to locate. Find it and replace it… Again I feel bad about how I just told you it was the Alternator I didn’t know you wouldn’t check for sure… :frowning: SO…remove belt and with your hand…rotate every piece of the system until you find the culprit.

**** UPDATE : You can also idle the engine with everything hooked up and see what component stops spinning? WIll that work or is idle not sufficient… Your A/c Compressor may be locked up internally…and then the A/C clutch my be cycling on and off…making the issue come and go…if the clutch locks up…and the compressor is seized…then upon lockup of the clutch…the pulley stops spinning…then when the clutch disengages…the pulley freewheels again… Could this be it?

Blackbird…feeling rather…BLUE :frowning:

Don’t worry about it – as I said, the Alternator tested with a bad diode, so that needed to be replaced regardless. This engine has two separate belts – one for power steering only, and the other for alternator and AC. My concern is that if it’s the AC, the compressor tore itself apart form the inside out, so I have aluminum shards throughout the system – a new compressor would get eaten alive and I don’t want to spend the big $$$ to replace all the A/C components.

If it’s not the A/C, then it’s the idler/tensioner. Regardless, I think I’m going to have to remove all the bottom plastic again. Hopefully it will be warmer and not quite so windy! ha ha

But I can only undertake all this when the symptoms are presenting themselves. As they are intermittent, …

So if it is the A/C compressor, and since I don’t use the A/C (too expensive to fix), is it theoretically and practically possible to bypass the A/C compressor by means of a smaller (i.e. shorter) belt (assuming an unobstructed belt path?

Yes that is possible…MAYBE…the path is the issue there… If its your A/C… then it should only be an issue when the A/C clutch is in lockup mode…otherwise it SHOULD freewheel for you. If you took another look at my previous post, I added to it my theory of if the AC clutch was turning on and off…thus making the pulley freewheel…then lock…freewheel…lockup…etc… It would be intermittent bec of the “cycling” of the AC clutch…and the seized internals of the compressor.

You need to see if the AC freewheels OK when it is electrically unplugged…it should…they rarely lock up like that…“that” meaning when the electromagnetic clutch is not energized…she should spin nice and smooth… SO when no clutch engaged it should then act just like an idler pulley…no need to remove the AC compressor…just leave it there UNPLUGGED…so that the clutch cant engage on and off. Get it?

Are you familiar with how the AC compressor and clutch function?

Ah – I like that solution the best – if as you say, the conditions you expect are indeed the case.

Well, stick a fork in me – I’m done for the night. Thanks for the great dialog re this topic.

A little recent history – about a month ago, my wife was t-boned in her 2006 Sienna when someone ran a red light running at least the posted speed limit of 50mph. That van is totaled. My wife is slowly healing with a few broken neck bones and some disc issues in her lower back. We have a replacement car on order, but we certainly can’t afford to replace two cars at one – which is why keeping this Honda Odyssey with 182,xxx miles on it running well is very important – at least to us.

That Ody will run a LONG time for you…Honda makes excellent vehicles…I’m one of their biggest fans. WELL worth maintaining…

So you do understand what I am saying about the AC compressor and its clutch? But why is the clutch cycling? do you have your defrost setting on? I believe that turns on your AC by default…and if you dont have sufficient ac charge the clutch will cycle…then if the compressor is seized internally…the pulley will lockup upon clutch engagement…again why is the clutch turning on? Unplug the thing and check its ability to freewheel… You can test my theory…PLEASE always test the theories here…as we are on the net… If I were in front of the vehicle I would be checking/testing multiple theories in seconds…quickly getting to the root cause…you know?

Yep, I certainly do. I don’t “hear” the A/C cycling on and off, and I make a constant effort to keep it turned off (“A/C Off” always displays in the window) even when the defroster is on (all due to the A/C problems). It’s either A/C or tensioner – we’ll get it.

Yeah no doubt you will find it… Just pull that belt and examine every rotating assy you have and you should find it sooner or later. Good luck and let us know what it was!

Midlc, I had the same thing happen to my 2000 Ody. with 285,000 miles on it. I also thought it was a bad alternator, that I replaced, but the dash board lights still came on intermittenly while I was driving. I needed to change the alternator out also, started to go bad.

I started to go down the road of replacing my catalytic converter but took the lazy way out after reading the difficulty of the task. I read through my maintenance record and realized that I never replaced my spark plugs since I bought the car. I changed the plugs and the problem went away. I love this car, I am hoping to hit 350,000 miles with very little problem.

So far, I replaced the transmission @ 121,000 and all the belts @ 230,000. I don’t take it to the shop but try to do most of maintenance myself. The rear heater coil had to be bypassed, started to leak @ 245,000. In Ca. I can do with out the rear heater, the fronts still work.

I hope this solves your problem. Good luck.