VOLVO
ABS-00A4 - Brake pressure sensor 1. Signal faulty. Intermittent fault
System
Anti-lock Braking System (ABS)
Volvo models this fault code applies to
Applies to the following models:
4 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007)
Show models by year and engine (4)
What does this fault code mean?
Brake pressure sensor 1 tells the ABS control module the pressure in the brake system. This code applies only to cars with stability control. At some point the module registered a faulty signal from this sensor, and the fault is intermittent, meaning temporary. The equivalent code for brake pressure sensor 2 is ABS-00A5.
Possible causes
- Open circuit in the wiring
- Wiring shorted to ground or supply voltage
- Sensor incorrectly fitted
- Faulty pressure sensor or, less commonly, a faulty control module
What you can do
- 1Check that the wiring to brake pressure sensor 1 is intact and not chafed or pinched
- 2Check that the sensor is correctly fitted
- 3Follow the wire to the sensor and look for intermittent open circuits
- 4Remedy as necessary and clear the code
- 5If the fault returns, have a workshop with diagnostic equipment check the pressure signal
- 6ABS and stability control are safety-critical – do not work on the brake system yourself, have a workshop do it
Symptoms you may notice3
- Anti-spin does not work
- Stability function is absent
- Anti-spin warning lamp lit
What the fault can affect2
- Anti-spin function is blocked
- Stability function is blocked
General guidance for car owners. Diagnosis on the car can point to a different cause.