Meaning for specific makes
The same number can mean different things for different makes. Below is the make-specific meaning.
Toyota, Lexus: VSC: ECM communication circuit malfunction
Don’t put off the repair
A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- The link between the ABS/VSC unit and the engine ECU: connectors, wires
- The engine ECU or the ABS unit
- Low voltage: a flat battery or corroded terminals
What you can do yourself
- Check the battery and terminals: at low voltage control units lose communication.
- ESP and traction control, and sometimes ABS, may not work. The brakes still work, but without electronic help — on slippery roads brake smoothly and don’t accelerate hard.
Stop and don’t drive on if:
- The red brake light is on, or the brake pedal feels soft or sinks
- The steering became very heavy, or the car pulls to one side when braking
OOleg’s tip: check the connector
Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.
Unplug and inspect connectors with the ignition off.
VSC is Toyota’s stability control system (the same as ESP). This is the Toyota and Lexus meaning. On other makes this number means something else: if your car isn’t a Toyota or Lexus, change the make at the top.
Source: Toyota 4Runner 1996–2002 repair manual (ether3al.com), static.nhtsa.gov
Hyundai, Kia: ABS/ESC: front right wheel speed sensor — open or short
Don’t put off the repair
A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
OOleg’s tip: it’s not always the sensor
It may not be the sensor itself but what it reads the signal from: the tone ring on the hub or axle shaft, or, on many cars, a magnetic ring that is built into the wheel bearing itself. Dirt, rust, a crack or damaged teeth, or bearing play — and there’s no signal even though the sensor is fine.
Remove the sensor and, turning the wheel slowly, look at the tone ring: are all the teeth intact and clean? Rock the wheel by hand — bearing play also disrupts the signal. The magnetic ring isn’t replaced separately: it’s part of the bearing.
Possible causes
- The sensor connector: dirt, water, corroded pins
- The sensor wire is chafed or broken — in the wheel arch, by the shock absorber or at the bend near the hub
- This wheel’s speed sensor
What you can do yourself
- With this fault ABS usually switches off: the ordinary brakes still work, but without ABS the wheels can lock. Brake smoothly and leave a bigger gap, especially on slippery roads.
- Inspect this wheel’s sensor and its wire up to the connector: dirt, corroded pins, chafed insulation. Clean the connector, remove the sensor and clean its tip and its seat of dirt and rust.
- Inspect the sensor harness near the radiator and under the headlight: per a Kia bulletin (Optima 2015) it chafes on a bracket.
- A scan tool’s live data shows each wheel’s speed: while driving, this wheel should read the same as the others.
Stop and don’t drive on if:
- The red brake light is on, or the brake pedal feels soft or sinks
- The steering became very heavy, or the car pulls to one side when braking
OOleg’s tip: check the connector
Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.
Unplug and inspect connectors with the ignition off.
Find the part on Kaspi ShopBefore buying, check the part number or match the part by VIN in the Kaspi “Garage”.
ESC is the Hyundai and Kia stability control system (the same as ESP). This is the Hyundai and Kia meaning. On other makes this number means something else: if your car isn’t a Hyundai or Kia, change the make at the top.
Source: Kia TT066 (Optima 2015), Kia Tech Times 2012 (static.nhtsa.gov)
Need a mechanic’s help?
Couldn’t fix it yourself? Oleg, an auto electrician, does computer diagnostics and repairs: he comes out anywhere in Almaty or sees you at his workshop.
Want to figure it out yourself?
Oleg’s course “Car computer diagnostics with a scan tool”: how to hook up a scanner, read codes and live data, and use them to find the cause. The first lessons are free.
Nearby codes
- C1112MDPS: torque sensor voltage errorHyundai, Kia
- C1200ABS/ESC: front left wheel speed sensor — open or shortHyundai, Kia
- C1201VSC: engine control system malfunctionToyota, Lexus, Hyundai, Kia
- C1202ABS/ESC: front left wheel speed sensor — no signal or invalid signalHyundai, Kia
- C1204ABS/ESC: front right wheel speed sensor — range/performance or intermittentHyundai, Kia
- C1205ABS/ESC: front right wheel speed sensor — no signal or invalid signalHyundai, Kia
- C1206ABS/ESC: rear left wheel speed sensor — open or shortHyundai, Kia
- C1207ABS/ESC: rear left wheel speed sensor — range/performance or intermittentHyundai, Kia
Who keeps this reference
The reference is kept by Oleg Dmitriev, an auto electrician from Almaty with 26 years of experience: computer diagnostics of cars and trucks, repair of control units (ECUs). Can’t find the cause? Message him.