[azmicheleh]

My hyundai sonata 2003, the ABS and TCS light always on... TCS light have off buttion but cannot suis off.

[TxGreaseMonkey]

The Traction Control System (TCS) Light may be turned on anytime the Check Engine Light (CEL) comes on, with the TCS system being disabled at that time. There may be nothing wrong with the system--the root cause is likely the CEL coming on, due to overfueling.

. Ensure the gas cap is tight. Tighten the cap 3 clicks, after seating the cap.

. Reset the ECM, by using a code reader or scan tool. Disconnecting the negative battery cable for 15 seconds may work--be sure to record any radio codes first.

. Stop pumping gas into the fuel tank, after the pump clicks off. Fuel may be expanding into the charcoal canister and throwing the TCS code. Topping the tank off, after the nozzle clicks, can result in serious damage to the charcoal evaporative emission system. If the charcoal evaporative emission system is damaged, repairs can run around $450.

If the TCS light and Check Engine Lights coming on is not related to overfilling the gas tank, it may indicate a more serious problem with the TCS System--likely involving the antilock braking system. Therefore, check the brake fluid level in the master cylinder reservoir. Only add an approved fluid, if the level is low. Don't add ordinary brake fluid--it's too viscous. ABS/ESC fluids are thinner and generate less heat in the small passages of the ABS/ESC pumps and modules. If, after resetting the ECM, the TCS light, CEL, and others come on again, take the car to Hyundai. They can determine if it's related to the charcoal evaporative emission system or to the brake system. My guess is that the problem is caused by overfilling the gas tank.

[this8384]

You have a problem with your anti-lock brake system, which is the only reason your traction control light is on as well.

Have a computer scan done to determine where the ABS problem is, have that problem repaired and then reset your computer.

[CaptainRich]

If there is a problem either with the engine control system or sensors, or with the anti-lock systems or sensors, that could be causing the Anti-Lock Braking System (ABS) to store a code and turn the ABS light on, thus triggering the Traction Control System (TCS) light to come on. The TCS cannot properly control traction if the ABS detects a fault. And the ABS will frequently interpret many Engine Control Module (ECM) diagnostic codes, and determines that the ECM-detected fault(s) could jeapordize ABS functions (those engineers are pretty smart, huh?) and turn on the ABS light and disable the anti-lock functions. You will most likely still have full brake capabilities still working beautifully!
Virtually any time the ABS light comes on, the TCS system will also determine that to mean, "the ABS isn't working, so we won't either!" And so, on comes the TCS light as well.

Find out what the codes are and let us know.

[perrylgl]

The code is
Scan abs, tcs module c2114 hecu module