Hi, I have owned an 03 accord Ex coupe for about 10 years now. Was kept in pristine condition when I bought it. Has 160k miles now. Runs great, always has.. I’ve kept up with general maintenance as per the manual - oil changes to tune ups, timing belt change, new parts when needed, new battery/alternator/starter/etc every so many years, mostly drive inner city, no major issues ever.

...but over the last 7 years I’ve noticed strange electrical failures here and there every so often..
for instance, one day my heated seat on drivers side light bulb just goes out,.. several months ago my blinking front turn signal lights when pressing the alarm on the key stopped working (meaning when I press my key and set the alarm and my horn honks and tail lights blink, now my front turn signal lights don’t blink along with it anymore), I’ve never really used cruise control but I’ve been using it for the last couple weeks and then one day it stopped working out the blue along with the radio controls on my steering wheel,... and some other similar issues...

I’ve checked the fuses, all good, I even put in some new relays not too long ago.. everything on the car runs fine and always has. Engine is really clean and battery, starter, alternator, are all fairly new still, no bad wiring or connections visible..

The only thing I can think of is if there was some sort of short or something when I tried giving somebody a jump several years ago and they had their cables on backwards, I saw sparks and freaked out, disconnected and did it the right way.. but nothing was wrong with my car back then after that.. things just began to fail every so often as the years went on..

Am I missing something? Could something be shorted or fried? Or could this just be aged parts dying due to wear and tear?
if so, why do my turn signals work but not when I press the alarm on my key?
I’ve been scratching my head on this one for a while...

 

In my 07 I started having electrical issues with a lot of things. I could not figure it out. Clock, radio lights would flicker ever once in a while. One day I decided to change my battery to the 6cyl one and change the ground cable to the one that came with the 6cyl. Once I sanded and cleaned the grind mount point and put everything back in I never had the issue again. I would say check and clean the ground points and see if it makes a difference.

 

Your car is 17 years old, so you may have to address some minor issues.

If the battery was hooked up backwards for more than an instant, you would have blown one of the big fuses (40A size) and a lot of items would not work.

I'd treat each issue an isolated incident.

The heated seat bulb just needs replaced. My TSX had the same issue around year 6 or 7. Bought a bulb at autozone and had to install into the socket.

How good are you with some electrical testing? You will have to chase down each item to determine the issue then repair. A shop manual will help with the electrical. You can get an 03 accord pdf from automanualsource.com for ~$22 is worth the investment.

 

Okay I think I will check the grounds and see what I can come up with. But what is meant by ‘the 6cyl battery’ because mine is a 6cyl.. ? Do you mean get the actually factory battery?

 

No I have a 4cyl and I put a 6cyl size in my car

 

Thats the thing.. I never thought to test the big fuses until just recently, and they are still good.

Yeah I can just get the light bulb, but it just seems weird that every so often something just goes out, especially my radio controls and cruise controls on the steering wheel. They’ve always worked but I never really used them until recently then boom they both go out.. it’s like something is drawing too much electricity or bad ground or something and when something gets power, it’s more likely to go out.

I do have a manual. And I’m pretty well versed with this car and when it comes to electrical testing I know the basics, but am also a fast leaner and self taught if I don’t understand something.

I’m really thinking this has to do with some sort of bad ground or short somewhere. All fuses and relays check out. Battery and alternator are less than a couple years old.. all electrical works fine but every so often something just goes out..

I just realized I do have aftermarket headlights.. do you think this can somehow cause issues?

 

If a big fuse had blown, you would have a ton of stuff go out. The big fuses protect large portions of the electrical system.

From your description, you had several unrelated instances over the last 7 years of owning the car. I do not think this is related to incorrectly jumping the battery, because you would have blown one of the large fuses.

Please tell us what is not working on your steering wheel controls. Does the radio still work and do the controls on the actual radio still work?

As for the front parking lights, do the front parking lights turn on when you turn the light switch to turn on the parking lights?