C008A: TCS Mode Control
What to do
The car drives and brakes normally on the road — what you may have lost is the off-road or surface-specific driving modes, with the system defaulting to its normal road setting. If you rely on those modes, do not assume they are working until it is fixed.
What this code means
The traction control mode control circuit has a fault.
Mode control is more than an on/off switch: it is the selection between calibrations tuned for different surfaces.
A modern vehicle may offer snow, mud, sand, rock and sport settings, and they are genuinely different strategies — how much slip to permit before intervening, how sharply to cut torque, how much lock-up ABS allows. Sand wants slip that tarmac must not have, and a setting that is right in one place is wrong in another.
A fault here normally leaves the system in its default road calibration. That is the safe failure: the car keeps the setting appropriate to tarmac and loses the special ones, so the consequence is being less capable off-road rather than less safe on it.
The selector is the usual suspect — a rotary knob or a set of buttons in the console, its wiring, or the module that reads it. Check whether the mode display changes when the selector moves; if it does not, the fault is on the input side.
Likely causes
Start here
- Faulty traction control switch · specialist
- Corroded or loose connector · specialist
- Damaged wiring harness · specialist
Less common
- Loss of communication with another module · specialist
- Faulty stability control module · specialist
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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