lonezodiac

I just purchased a 2003 with 146000 everything works great and the car looks brand new, but starting yesterday i started getting a weird issue with the brakes. When i brake at any speed i can hear a clicking/buzzing sound and the pesal starts to pulse also my speed when im driving is all crazy. Need help on this issue and how to fix it if anyone has any idea what it is thank you

dkmura

iTrader: (64)

Welcome to the board, but you'll need to polish up your spelling/writing if you're going to get any answers. What do you mean by "my speed when im driving is all crazy"? Is your tach and speedo not functioning properly? If so, it's likely a different issue from the brakes.

What kind of condition are your pads and rotors in? If you're having a clicking/buzzing issue with ABS kicking in under light pedal pressure, it's more likely warped/worn rotors and possibly pads, than an electrical issue.

taywan

iTrader: (53)

Sounds like one of the front abs wheel speed sensors bad or going bad

terrasmak

iTrader: (8)

Speed is taken off the rear sensors, that would be where I would start.

taywan

iTrader: (53)

My vdc/slip/abs comes on after a while of driving, turns off after I restart. Then it comes back on after a little while. I thought when the brakes are pulsing it would narrow it down to the front sensors but no brake pulsing would narrow down to being one of the rear sensors???

dkmura

iTrader: (64)

OK- so now YOU have brake problems as well as the OP? In your case, it would be better to use the diagnostic side of your ABS controller. Hook up a code reader and go to the ABS side (I use UpRev's Cipher- it's quick and easy) to see what codes are held in memory. That'll narrow down the possibilities, rather than guessing as you're doing now.

taywan

iTrader: (53)

I don't have brake pulsing issues at all. That's what I've read is why I suggested that. Didn't say o was correct. I just haven't had the time to this weekend BC its not a huge deal as nothing is wrong and the car drives perfect. I will grab a friends good scanner that has the data stream and abs scanner on it also in a day or so to pinpoint my sensor prob.

LanZe

I recently had the every popular ABS/SLIP/VDC lights on, when I got it onto a suitable ODBII reader it showed a C1142 ABS pressure sensor circuit fault.

The symptoms were inconsistent for about 6 months before finally completely failing. So I'm not sure the systems behavior is a very good diagnostic tool.

If you wind up in a similar situation look for a salvaged ABS pump that has the same feature as yours (VDC and TCS for instance). I got mine for $120 shipped. Install requires triggering the ABS' unit's brake bleeding program so make sure your preferred shop knows what they're doing.

taywan

iTrader: (53)

Now finally some good info/help. Thanks. Actually tried data streaming and wheel sensors all read consistent mph's. I sure did receive the codes: C1142 - pressure sensor circuit and c1116-stop lamp switch. Did you receive that also???

jankypr350z

had same problem. was the abs sensor. new is $100+. got mine of ebay for $15 used. has been installed almost a year no problem

LanZe

AFAIK C1142 means your ABS unit is toast. I tested mine in a rainy parking lot and it was absolutely non functional while that code was present.

OEM price for a new ABS unit is about $1100. Check somewhere like Automotix.com to find a salvaged unit. Theirs come with a 1 year warranty. You need to make sure that you get one that has the same features as your car. I have VDC but no TCS for example. Install is about 4 hours labor, but they need to be able to make the ABS unit run it's own bleed software otherwise the pump will be full of air. Also note that the ABS unit is shared with the G37, you can find the parts numbers (mine was 47600 AM400) engraved on top of the ABS unit, the G37 one has the same parts numbers. There are a couple of other numbers which are different, but I don't know what they're for, maybe revision or feature set. There's also a serial number on top.

As for C1116 I had that as well, and my brake lights were very very dim. It didn't show up until about 8 months after the ABS unit started failing so I don't know if the two are related. Park your car somewhere dark with the back facing a wall, or inside a dark garage. Turn off your tail lights, reach into the car and stand on the brake pedal. Are your brake lights dim and does your center brake light work? For me the answer was very dim and no the center brake light didn't work. Oddly the behavior changed when the tail lights were on, the brake lights were still dim but the center one worked, but only when the tails were on. Weird. I had the 2006 LED tail lights installed in my 2004 Z, so I swapped back to the original incandescents and they behaved correctly. I haven't tried putting the LED units back in since I had the ABS pump replaced so I don't know quite what the problem is. My guess is that one of the LED tail light's electronics was failing and needs to be replaced. Haven't had time to spend figuring it out.

taywan

iTrader: (53)

Did some more research last night.
The abs and brake lamp switch are related as if you get both, the reason could be the lamp switch triggers the abs,slip, and vdc to come on. Some have replaced brink lamp switch--fixed. I did that today for my trial/error and no more codes from abs system. Auto zone=$29.99. Advanced was $39.99. So far so good but need to do some more driving tomorrow. Will drive to work/home/ dinner and see what the results are. I drove tonight foe couple miles and nothing came back on but sometimes it takes longer to do so...will post updates to help any others w this issue. Thanks for the helpful posts-lanZe

Edit: this issue is quite frustrating as I've read it could be numerous things: abs wheel speed sensors, abs pump, solenoid, stop lamp switch