TCS lights stay on for no reason?

Brakes feel fine after

I really appreciate your sharing your issues. If I had not read your post regarding the tcs/dsc light coming on I would not have known to tell my dealer to contact MazdaTech. This was my fourth trip to my dealer regarding the light issue. I do not think they would have contacted MazdaTech had I not mentioned your post. Anyway, the hydraulic control unit was replaced on my 2010 CX-9 yesterday. I immediately noticed a difference in the braking. There is a lot of play until the car starts to slow down. I phoned the dealer and he said the braking will now be "soft" because of the part replacement. It doesn't feel safe to me. I spoke to an auto mechanic and he said it sounds like the brakes need bleeding. He doesn't think the dealer's explanation is correct. My question to you, did your braking change after the hydraulic control unit was replaced? Thank you for all your information.

I actually find the brakes more responsive after the tsb
 
Hi Antonio, I have same problem with TCS (sometime TCS switching off together with the light that comes on when TCS is engaging) . I call Mazda service in my town but they ware not able to find this TSB. I contact Mazda general office but they replay to me that this TSB is not for my car (I have limited 2010 European version). Because you have such nice contact with your dealer can you get this TSB in pdf format, then we can see if this TSB is limited for number of cars by VIN number. Maybe if I show this to service then they will try to replace this Hydraulic/ABS control unit.
 
Took my 2010 CX-9 into the dealer because the TCS and DSC indicators would illuminate periodically. I didn't mention this TSB, but thats what the receipt shows - TSB 04-002/11 - replace ABS/DSC hydraulic unit.
 
Took my 2010 CX-9 into the dealer because the TCS and DSC indicators would illuminate periodically. I didn't mention this TSB, but thats what the receipt shows - TSB 04-002/11 - replace ABS/DSC hydraulic unit.

OK and Thanks
 
Took my 2010 CX-9 into the dealer because the TCS and DSC indicators would illuminate periodically. I didn't mention this TSB, but thats what the receipt shows - TSB 04-002/11 - replace ABS/DSC hydraulic unit.

Well, after the repair my brakes are really mushy. My wife and I noticed it independently; I asked her if she noticed anything different, and she mentioned the poor braking. So its going back tomorrow... a major PITA since I'm 1.5 hours from the nearest dealer!
 
Brought the CX-9 back, they bled the brakes and its back to its normal. The service manager said they used the "automatic" method the first time and when I brought it back they manually bled the brakes.
 
Bringing mine in tomorrow for the TSB, along with the console padding (2nd time). Will update how it goes. Gotta remember to make sure that they bleed the brakes. Might be a silly question, but do they bleed all 4 brake lines?
 
Service Tech did not see anything on the TCS diagnostic that would warrant the action on TSB. He was asking me if I was turning hard with the CX-9. I told him that I was going straight both times the TCS light came on. I also said that the CX-9 is too big of a vehicle to throw around corners like my 2007 VW GLI, and my VW hasn't thrown a diagnostic light due to spirited driving.

I might try a different dealership if the TCS light comes on again.
 
Service Tech did not see anything on the TCS diagnostic that would warrant the action on TSB.

It wasn't just the TCS light for me; it was the DSC too - it looks like two squiggly lines up in the top center of the dash. It was the presence of the DSC indicator that was concerning - it only comes on when there is a problem with the stability control (TCS is traction control).
 
+1 djc6. The TSB covers the issue when tcs and dsc illuminate together. The tech maybe right. Crikey do you have AWD or FWD? FWD could conceivable slip the front wheels when entering a corner under heavy throttle since there are no rear wheels to engage. Happens with my Mz6 sGT frequently when I apply throttle going around a turn and the wheels spin. Just a thought.
 
+1 djc6. The TSB covers the issue when tcs and dsc illuminate together. The tech maybe right. Crikey do you have AWD or FWD? FWD could conceivable slip the front wheels when entering a corner under heavy throttle since there are no rear wheels to engage. Happens with my Mz6 sGT frequently when I apply throttle going around a turn and the wheels spin. Just a thought.

I have FWD. I had the TCS/DSC Indicator light come on when the issue occurred.

I can see entering a corner under heavy throttle with a Mazda6, but with a CX-9? The vehicle is heavy and it would be against my better judgment to throw it around corners eventhough the CX-9 is more than capable compared to its CUV peers. Also, like I mentioned, I was going straight both times the issue occurred.
 
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I have FWD. I had the TCS/DSC Indicator light come on when the issue occurred.

The symptoms exhibited by my car was that you'd turn on the vehicle and the TCS/DSC lights would come on and both stay on. Then a few days later, they'd go off. Then a couple weeks later, they'd come on for a few more days. They didn't come on as a result of any maneuvering.
 
Usually when the DSC/TCS light comes on, likely one of the two in the following is bad
- ABS pump/control unit
- ABS lockup sensor
If it goes on and off, more likely it is the latter.

Just my guess of course. If there is a light on the dash, there is an error code. A diagnostic device and dig out the code.
Do you have a NAVI system?
If yes, I can tell you a procedure (works for '07 and '08, not sure about later models) to display the error codes existing
in the OBD. No external device is needed.
Otherwise, you can go to AutoZone or Kragan Auto. They can read the codes for you for free usually.
 
Usually when the DSC/TCS light comes on, likely one of the two in the following is bad
- ABS pump/control unit
- ABS lockup sensor
If it goes on and off, more likely it is the latter.

Just my guess of course. If there is a light on the dash, there is an error code. A diagnostic device and dig out the code.
Do you have a NAVI system?
If yes, I can tell you a procedure (works for '07 and '08, not sure about later models) to display the error codes existing
in the OBD. No external device is needed.
Otherwise, you can go to AutoZone or Kragan Auto. They can read the codes for you for free usually.

The service tech has reset all of the codes on my last visit, so the current plan is to wait until the lights come on again. I don't have the NAVI system also. I'm just concerned that the TCS and DSC lights came on for, seemingly, no apparent reason, and being unable to re-enable the TCS using the TCS button.

On both occasions, restarting the vehicle cleared the indicator lights. I'm gonna have to wait until the lights come on again.
 
The symptoms exhibited by my car was that you'd turn on the vehicle and the TCS/DSC lights would come on and both stay on. Then a few days later, they'd go off. Then a couple weeks later, they'd come on for a few more days. They didn't come on as a result of any maneuvering.

I don't experience the symptoms you describe. On our CX-9, the indicator lights lit up on 2 occasions for no apparent reason, and there was no way of re-enabling TCS when the lights went on.
 
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