What does the circle with the letters TC mean on the dash

Do you have a hand book for the vehicle this will be explained in more detail. TC = traction control this is to do with your braking sytem. You may have a switch for this normaly down by the gear change or on dash by stearing wheel normaly on right side of stearing wheel. If you locate switch turn it on and off if this either turns light on or off all should be ok turn traction control on and leave it on, if light stays on in either possition of switch take to a holden dealer as there will be an issue. probably a front wheel speed sensor playing up but please get it fixed as it is a very important safety issue. good luck.

Antilock Brake System, If its by it's self it means there is a fault. If accompanied by the regular red brake light normally means the problem is with the regular hydraulic part of the braking system. It also means your Antilock system has been defeated.

tc stands for traction control . with car started and foot on brake open glove box and push the tc button. I believe it should engage/disengage this feature but im no expert so refer to owners manual first, I think it acts kinda like a mock transfer case?

Should consult manual but usually this symbol means either tire pressure or could be brake pad wear if it has a circle with another circle around it such as -- (O)
Sometimes this could also mean your ebrake is engaged. Even if it is not engaged the sensor could be bad.

where were these letters circled.....?????

Hello: TC Means traction control. It would be best to check for symptom codes with a upscale scanner to find out what is causing the code. Make sure there isn't a switch to turn the TC system off. Check above the center console on the center dash panel for the switch, may have TC on it.

TC= traction control
ABS= anti lock brake system

explanation in the user manual

TC STANDS FOR TRACTION CONTROL. ITS SENSING THE WHEELS SPINNING(LOSE OF TRACTION.)A COUPLE OF CAUSES ARE THE WHEELS LOOSING TRACTION(ICEY ROADS)
THESE CARS ALSO HAVE FRONT WHEEL SPEED SENSOR WIRING PROBLEM, NEED TO CHECK ABS SYSTEM FOR CODES TO NARROW DOWN WHICH WHEEL IS A PROBLEM.

Hello!

A sign like this indicates that your parking brake pads(shoes) are worn, and are in need of replacement.

A sign like this indicates that there is problem with the ABS system (can be anythig from a faulty wheel speed sensor to a burnt out fuse)
A non functioning ABS could bring the tires to a lock up during extreme braking which could be rather dangerous.

Hope this helps!