What it means
The control module monitors supply voltage circuit A for the ABS pump motor. It sets this code when the voltage is lower than the expected range.
At a glance
- Usually lights the ABS or stability-control warning light
- The engine or gearbox may go into limp mode
How it works
The ABS control system monitors supply voltage circuit A for the ABS pump motor, which helps build hydraulic pressure during ABS operation. This code sets when circuit A voltage falls below the expected range, so the pump may not receive reliable power.
Common causes
Most likely first.
- Weak battery or low system voltage
- High resistance in wiring or connections
- Blown fuse or poor fuse contact
- Control module fault
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
How to diagnose it
- Record ABS freeze-frame data and check battery voltage and system voltage to see whether low supply voltage affected circuit A.
- Inspect the battery condition and charging system for a weak battery or inadequate charging that could lower ABS supply voltage.
- Check the ABS pump motor supply circuit A fuse and its contacts for a blown element, corrosion, or poor seating.
- Inspect circuit A wiring and connectors for looseness, corrosion, damage, or excessive resistance.
- Measure voltage in circuit A at the ABS unit under the manufacturer’s specified test conditions to locate the voltage drop.
Common fixes
- Charge or replace a weak battery as indicated by testing.
- Replace a blown circuit A fuse after checking for the cause.
- Clean and secure a poor fuse contact or ABS connector.
- Repair damaged or high-resistance wiring in circuit A.
- Replace the ABS control module only if circuit voltage and connections meet specification.
Can I keep driving?
The vehicle may still brake, but ABS and stability control can be disabled. Drive cautiously with extra stopping distance, especially on wet or loose surfaces, and address the low supply promptly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.