VOLVO
ECM-1818 - Engine cooling fan (FC) relay, 1/1 speed. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS40 (1996–2004), V40 (1996–2004)
Show models by year and engine (2)
What does this fault code mean?
The ECM drives the relay for full speed on the electric cooling fan. If the control signal is too low, because of a break or a short to ground, fault code ECM-1818 is set and the fan does not run at full speed.
Possible causes
- Control signal wire shorted to ground
- Open circuit in the control signal wire
What you can do
- 1Check that the connectors to the full-speed relay are firmly seated and free of oxidation
- 2With a multimeter, check that the control signal wire is not broken and not shorted to ground
- 3If you have a diagnostic tool: activate the cooling fan at full speed and check that it starts
- 4If the fault remains, have a workshop replace the full-speed relay
Symptoms you may notice1
- The cooling fan does not run at full speed
General guidance for car owners. Diagnosis on the car can point to a different cause.