ABS Rear Inlet Valve Coil Circuit Failure
The C1206 code indicates an electrical fault in the rear axle ABS inlet valve coil circuit. This valve controls hydraulic pressure to the rear brake caliper during ABS modulation. The ABS control module has detected an open circuit, short to ground, or short to battery in the coil circuit. Since the valve is integrated into the ABS hydraulic module, this fault prevents proper brake pressure control at the affected rear wheel.
1. Commonly Affected Makes
2. Most Common Causes
- Damaged or open internal rear inlet valve coil in the ABS module
- Faulty ABS control module (ECU integrated with valves)
- Corroded, broken, or disconnected wiring or connector between the ABS module and ECU
- Short to ground or battery in the rear inlet valve harness
- Coil resistance out of specification due to thermal degradation
- Poor ground connection of the ABS module
3. Symptoms You Will Notice
- ABS warning light illuminated on the dashboard
- Reduced or no ABS function at the rear wheel, potentially causing wheel lockup during hard braking
4. Step-by-Step Diagnosis
Scan the ABS module for fault codes and record freeze frame data
Visually inspect the ABS module connector and wiring for corrosion, damage, or loose connections
Measure the resistance of the rear inlet valve coil at the ABS module connector; compare to manufacturer specifications
Check for shorts to ground or battery voltage on the valve control circuit
If wiring and resistance are normal, suspect internal module failure and replace the ABS hydraulic module/assembly
5. Frequently Asked Questions
Is it safe to drive?▼
No, it is not safe to drive. The ABS system may not function properly on the rear wheel, increasing the risk of wheel lockup and loss of control during emergency braking. Have the vehicle towed to a repair shop.
How much does it cost to fix?▼
Repair costs typically range from $200 to $1,200 depending on the cause. If the ABS module needs replacement, parts and labor can be $500–$1,200. Wiring repairs are usually $200–$400.