VOLVO
AEM-5F20 - Remote start. Signal too low. Permanent fault
System
Accessory Electronic Module (AEM)
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?
The AEM has registered a signal that is too low on the supply to the remote start unit, and the fault is permanent. The remote start and therefore the parking heater does not work. The cause is usually a short to ground in the supply wire or a faulty remote start unit.
Possible causes
- Supply wire to the remote start unit shorted to ground
- Faulty remote start unit
What you can do
- 1Follow the supply wire to the remote start unit and look for chafing or damage
- 2Check that the battery is charged and that its terminals are tight
- 3Check the connectors at the remote start unit for oxidation and loose connections
- 4If the fault remains, have a workshop replace the remote start unit after checking the wiring
Symptoms you may notice1
- Parking heater does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.