30,000 miles. The brake light just started coming on. My brakes appear to be functioning fine. What could this indicate? Is it a warning to get new pads? Thanks John

 

Brake light on the dash is for brake fluid low or for the emergency parking brake.Inspect the brake fluid .If it is low and you are still in warranty bring it to the dealer for further diagnosis. Sometimes the rear wheel cylinders will leak and causing fluid to go low. Front brake pad wear will also cause fluid level to drop. If the emergensy brake switch shorts out this will also cause the light to malfunction.

 

Last message here is over 4 years old, so I don't think I am hijacking this thread, but I have a question on the brake light indicator, 2000 Sonata 2.4L 4 cyl.
The other day the "Brakes" and the symbol for a battery came on in red in the i.p.

I looked up the schematic, and found that the two lights are tied together with a diode, but I figured it was a misprint, showing the cathode on the brake indicator and the anode on the battery indicator. Didn't seem logical.

So I looked into the brakes, it wasn't the parking brake switch, had to be the brake fluid level sensor. Brake fluid level was fine. Took off the wheels, the pads and shoes were better than fine, pads looked new! Brakes worked fine too. So I figured it must be a faulty sensor, but I couldn't get the connector off to see if it made the light go out, besides it was a bit intermittent, which is frustrating.

I even pulled the i.p. and saw the diode, at least from the silkscreen side of the flexible circuit board, and it matches the schematic, hmmm.

So yesterday, Mom and I set out on the way to-baby sit my grandkids, it died, battery dead. Oh,... now it all makes sense, it was the alternator, probably the slip rings losing contact (Intermittently at first) and the diode is in the circuit adding the "Brake" warning to it. So now, after I retrieve the car, I will fix the alternator.

This was never a problem before the handy-dandy warning lights were there to lead me astray, if the brakes didn't work it was easy to tell, and a little exciting too. If the Generator didn't work, you would figure it out when the 8-track would slow down, and Bobby Darin would go bass.

So anybody know why they tie the two together? If it was to frighten me into action, it was effective, but it sidetracked me from the real problem. I have heard "it is a shame to waste a crisis", is this what they meant?

Thanks for your speculation...and a littly sympathy wouldn't hurt either...

 

you're some sort of retired engineer, right?? now you realize i have to get into my mothers car to see what, exactly, these lights are, and how they relate to one another on the dash.

oh, and i love the 8-track and bobby darin references. i remember seeing a firebird from back in the day when i was knee high to a steel belted radial that has the 8-track, radial tuned suspension, and the sparkly dash pattern. thanks for taking me back.


oh yeah, didja git that thar batry fixtchet??


df

 

That's hilarious, I enjoyed that. You realize that a "retired engineer" is an oxymoron, but you nailed it!

To get the effect of misdirection, you would have to have an Alternator failure, which turns on the battery symbol. The problem is it also turns on the same "brake" word that you get if you pull on the parking brake, which is easy to see, or run low on fluid, which I hope you don't see.

Of course you can see both if you turn on the key but don't start it.

I still don't have the i.p. bolted back in, so I will cut the diode so we have two distinctly separate indicators, it was silly.

Thank you for appreciating my comments, now you see where the moron part of the retired engineer comes out.

Had to get a rebuilt alternator, the regulator went out, and a new one was 3/4 the price of a whole rebuilt alternator, go figure... I would have gotten only a 3 month warrantee, but with the complete unit I get lifetime...

That goes in tomorrow. Then I have a remote start to put in. I am stalling, because I need to treat the engine cradle to rust proof it. It is in perfect shape, but won't stay that way now that the car has left N. Dakota, and lives in S.E. Mich (salt) My order of CorrosionX is in the mail.

 

Got the new alternator in, and I described it on post 5 here:
https://www.hyundaiforum.com/forum/s...ead.php?t=7200
Thanks for the help, PlanetDude came through for me.

Now I go rip out that diode...

 

there are 'redundancies' in the systems of many vehicles that wouldn't seem to make sense. i remember a truck that i worked on one time that had no blower motor function. the prior techs were replacing the blower motor, resistor pack, head unit, et all, and *still* no blower function.

that's when i got it. (yay me.....)

i pulled the wiring diagram and the oil pressure sending unit was a ground in the circuit for the circuit (i forget exactly how now as it's been years). put a new sending unit in and viola, full blower function. it was wired that was as there were no guages on the dash, just the lights. nobody, including myself, noticed before hand if the oil pressure indicator light lit up on the dash when starting the vehicle.

i have seen other circuits that did similar things, and it seems that they always tied into something that would be more obvious than not, but an oil pressure guage would have been nice.

good luck with the remote start.


df

 

Strange indications, I believe in more straightforward indications, as it saves a lot of grief. I remember when we had real gauges, like in an airplane. Don't know why we keep losing them. I hope the airplanes don't start that silly trend.

Got most of the remote start working. It was real easy on this car, most of the wires go to the ignition switch, no transponder bypass needed. Door lock wires went to the two door lock relays, just a dab of solder to pin 85 on each ("pull down" side of the coil)

Still finishing it up...