DoubleGoose

iTrader: (10)

So ive been having this problem lately where whenever i turn on the headlights (even just the parking lights) The TSC light (car with squiggly lines icon) and the ABS light come on. At first i figured it was a slight problem i could deal with and prolly something minor, but after todayi realize that when this happens it actually disables the Traction control, but only when the lights are turned on. I didnt think id make a thread about this quickly until just about 20 mins ago, i did a 180 on a highway in the rain cuz my traction control was not active and the back end slid out and i eneded up drifting before doing a 180 to a complete stop.

If it helps at all when i have my accessport plugged in, it shows PCM P0571 "Cruise control/Brake Switch 'A' Circuit Malfunction" If anyone could tell me where in the electronics i can start my diagnosis that would really help a lot. Thanks in advance!

dannobre

iTrader: (3)

WOW.....Must be a harness problem....

Do you have the electrical PDF? I can give you a mediafire address for it

http://www.mediafire.com/?5nn4qqnmm5o

tubingchamp

iTrader: (3)

Did you check your battery terminals?

Could be something messed up there. Though, never heard of that actually DISABLING TSC...

The only thing in common with that is when you d/c your battery, the lights stay on for a couple drive cycles.

Odd, man. Glad to hear you didn't get in an accident too.

DoubleGoose

iTrader: (10)

im thinking it has to be a harness problem or something along the way. It only happens when i turn on the lights, meaning it is something that that ties both the headlights and ABS/TSC together. When driving during the day and using no lights, those two warning lights never come on and the car rides fine.

zoom44

clearly there is a short. most likely in a harness under the dash having to do with the CC and braking as the "Cruise control/Brake Switch 'A' Circuit Malfunction" cel indicates. but of course it could be int he engine bay too. i dont have a diagram to look at quick

what have you changed in your car prior to this beginning

DoubleGoose

iTrader: (10)

i looked through all the fuses in the fuse box, and the relays and everything seems to be fine.

But yes zoom, i have a crap ton of wires that are wired in the driver side footwell..(turbo timer, power and ground for 5 gauges, footwell lighting, and various other electronics..it is a cesspool of wires down there. Any ideas which harness to start looking at down there? cuz im 98% sure the problem lies in that area, and its def a short of some kind.

zoom44

what did you do last? start there and start with the grounds. i doubt its the footwell lighting but ya never know.

Zitman

Did you ever solve this, because Im having the same problems and nobody wants to touch it

Razz1

Give us a list of your mods.

Hesselrode

iTrader: (3)

Does an LED third brake light throw this code

Harlan

iTrader: (3)

+1 for grounds. Something this screwball only comes from bad grounds.

BigKid

iTrader: (5)

Mine is doing the same thing. I'm wondering if it is the brake switch itself?

DoubleGoose

iTrader: (10)

wow thread Resurrection! Anyways, i sold the car awhile ago, but i did find the problem is this might help anyone. I put in LED taillight bulbs in, but the driver side taillight had heavy condensation due to some sort of leak in the gasket, it was like a fish tank in there. The water in there cause some sort of short in the system (Dont ask me why the rear lights are connected in the same circuit as the TSC because that boggles me.). Long story short, i replaced the bulb, checked the load resistors, got rid if the water, sealed it up, and everything was back to normal. Hope this helps someone!

fc2se

iTrader: (2)

I've had a similar problem recently and thought it was due to a loose battery cable. I adjusted the battery cables, but today I had the problem again. Here's what happened: At a random time while I was not using the brakes, the ABS and TCS lights came on. Sometimes when this happens, the radio also shuts off for a few seconds. This behavior seems to happen most when my headlights are on and it is raining, but I can't completely nail down what it takes to make it repeat the problem. The last time this was an issue was over 1 year ago (similar weather).

Earlier this summer I cleaned and sealed my tail lights which had gotten water in them, and they have been dry since then. I also do not have any LED lights (tail, trunk, side markers, etc.). I have read many threads on here that seem related to this problem including one where a harness connector had some corrosion in it:
https://www.rx8club.com/series-i-trouble-shooting-95/power-steering-failure-107481/
but that issue was related to power steering (which doesn't seem to be a problem for me).

Based on the wet weather, I'm suspecting something similar to what was stated here by DoubleGoose, so I do appreciate the update even though he no longer has the car. If anyone else has solved a similar issue, feel free to comment.

Hesselrode

iTrader: (3)

Just a little bit of my experience. My MAF sensor caused those two lights to come on. Replaced the MAF and it solved my issue. Also, when you disconnect the battery it causes this issue once first started. Maybe your battery is close to being dead, or maybe your altenator? I don't know this for sure just a thought.

fc2se

iTrader: (2)

Thanks for the note about the MAF and the battery/alternator possibilities. The unloaded battery voltage is 12.25 V, so I'll need to have it tested to see what is like under a load. I don't have a voltage reading for when the problem happened since I don't have a gauge for that (all stock gauges). Because of the radio and its display turning off for a few seconds when the problem occurs, I'm suspecting that a power loss occurs momentarily on that circuit. Also, unlike some reports, my problem occurs for only a few seconds and then goes away. I do not have the problem where the ABS/TSC/DSC lights stay on all the time.

I don't know why it took me this long to think of it, but I can test the idea that a momentary loss of battery power while the car is running is the source of the problem by disconnecting the negative terminal while it is running. I suppose what could be happening is that the battery loses contact while the car is parked, and then this issue arises once the car is started. (I can test that too.) Does anyone know if the TSC/DSC being activated causes the radio to shut off? It might make sense for that to happen to alert the driver over and above the dash light.

I hope I can rule out the simplest possible explanations first. I've had this car for over a year, and I was hoping that it would have fewer electrical problems than my FC (RX-7). On that car I spent a couple of years repairing and replacing a lot of the electrical components (ECU solder joints, interior switches, upgraded to FD alternator, etc.) and got it to be fairly solid except for the fact that the headlights and interior air blower fan seemed to cause unusually high loads on the electrical system which pulled down the idle RPMs. So far, this problem is the only one I've had with this car, so I'm keeping my fingers crossed that I can resolve it.

Hesselrode

iTrader: (3)

My car will not run without the battery. I don't know if this is all 8 or not. Do u have navigation? If so u can check voltage with it. Go to system info, then it's either down down up up or vise versa on the navigation pad. A lot of cool stuff there!!

Hesselrode

iTrader: (3)

Another thing, my car bogs with fan or headlights for a second.

fc2se

iTrader: (2)

I don't have navigation. I'll let you know if my car will run without the battery connected, and I'm going to have the battery checked at Advance Auto (and will likely replace it if it is weak). I did notice a slower and more difficult start yesterday after my car had been outside in less than 20 deg F weather all day, so maybe my battery is just about worn out.

I don't notice any changes to RPMs of the engine when I turn the headlights on. On my FC that problem seemed related to the upgraded headlights (higher current draw) and I think the alternator belt would start slipping once the car was warmed up. (I was able to "fix" the bog on the FC by overtightening the alternator belt, but that "fix" will end up wearing out the alternator bearing. So I just bought a new belt and put it back to the stock tension. The problem was lessened by the belt replacement. My instinct is to suspect a loose and worn alternator belt in your case, Hesselrode.)

Mazurfer

Yes, it can.......some get away without a resistor and some don't. Of course this would be independent of the issue the OP is having with the headlights......or it should be independent of that. See my thread for more info in this regard.
https://www.rx8club.com/series-i-trouble-shooting-95/have-abs-dcs-tcs-issues-lights-staying-202843/

fc2se

iTrader: (2)

Thanks for the note, Mazurfer. I found your thread the other day and am subscribed to it.

As for my problem, I now believe that it was caused by 3 actual issues that I found: (1) loose ground clamp on battery, (2) dying battery + cold weather, and (3) very corroded positive clamp on battery. I replaced the battery with a new Optima Red Top, cleaned the clamps, and made sure everything was tight. The car started up much more quickly than it has recently, and it drives great.

I'll post back here if the original problem happens again.

Mazurfer

^...............good news.

maniac0905

i feel so lucky when i found this topic and every1 is sharing experience to help the others.
I have a very similar problem to this so hope can get some help from u guys.
I just install an aftermarket CCFL Halo headlight 1 week ago and replace the brake halogen taillight with LED bulb. The car was very fine until when I adjusted the beam heigh last nite. The ABS comes up straigh away when I just turn the headlight on (even when I just turn on the parking light).

What I have tried: Shut the car down, turn on parking light, start the car, turn on headlight --> no ABS comes up. But after 100m driving, the ABS comes up.

I also have some footwell and underhood LED aswell, but I have disconnected all its wires after this things happen because I think it would be because of shorting. But nothing changed, ABS still comes up when light is on.

I also see some blue-white powder arround the battery terminals, is this bad and cause to the problem?
Please help. Thanks in advance.

Mazurfer

Sorry, haven't been on the site in awhile.

Battery corrosion is not the likely cause, but clean the terminals and posts up anyway.

Bounce over to this thread and work your way down the list.

https://www.rx8club.com/showthread.php?t=202843

However..............I can't tell if you put the LED in the third brake light position or not. I would take that out and the "new" headlight first and see what happens.