VOLVO
ECM-2682 - By-pass valve. Signal too low
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
2 modelsS40 (2004–2013), V50 (2004–2013)
Show models by year and engine (2)
What does this fault code mean?
The engine control module (ECM) monitors the bypass valve signal in the thermostat housing. If the signal is too low, the code is set. The cause may be poor contact, or an open circuit or short to ground in the signal wire.
Possible causes
- Contact resistance or oxidation in the connectors
- Open circuit or short to ground in the signal wire
What you can do
- 1Read the code, clear it and road test the car to see whether it returns
- 2Check that the connector at the bypass valve is fully engaged and free from oxidation and contact resistance. No rust solvent spray or grease
- 3Use a multimeter to check that the signal wire has no open circuit or short to ground
- 4If the fault returns after clearing and a road test, and no cause is found, have a workshop replace the bypass valve
Symptoms you may notice2
- The electric cooling fan runs all the time
- The air conditioning does not work
General guidance for car owners. Diagnosis on the car can point to a different cause.