VOLVO
UEM-00A4 - Tire pressure sensor. Low battery voltage
System
Upper Electronic Module (UEM)
Volvo models this fault code applies to
Applies to the following models:
5 modelsS60 (2001–2009), S80 (1999–2006), V70 (2000–2008), V70 XC / XC70 (2001–2007), XC90 (2003–)
What does this fault code mean?
The upper electronic module (UEM) receives messages from the tyre pressure sensors, including the internal battery voltage of each sensor. The code is set when the message from the first of the four approved sensors shows too low a battery voltage. The pressure for that wheel can then not be monitored.
Possible causes
- Low battery voltage in the tyre pressure sensor
What you can do
- 1Have a workshop activate the sensor for the affected wheel with diagnostic equipment.
- 2If the sensor gives no answer, its battery is likely flat or the unit has failed: have a workshop replace it.
- 3Clear the code and check whether it returns.
Symptoms you may notice2
- Message in the display
- The tyre pressure monitoring warning lamp lights or behaves abnormally
General guidance for car owners. Diagnosis on the car can point to a different cause.