VOLVO
ECM-68AD - Bypass valve, intercooler. Faulty signal
System
Engine Control Module (ECM)
Volvo models this fault code applies to
Applies to the following models:
3 modelsC30 (2007–2013), S40 (2004–2013), V50 (2004–2013)
What does this fault code mean?
The engine control module (ECM) monitors the charge air cooler bypass valve and how closely it follows its position. If the valve deviates too much from the position the module has calculated when it opens or closes, the code is set with the ignition on. The cause may be poor contact, a lead that is shorted or broken, or a valve that binds or is damaged.
Possible causes
- Loose connection, contact resistance or oxidation in the connector
- Open circuit or short to ground or supply voltage in the leads to the bypass valve
- Bypass valve binds or has jammed
- Damaged bypass valve
What you can do
- 1Look for visible damage and dirt at the bypass valve, since dirt can make it bind
- 2Check the connector at the engine control module and at the bypass valve for loose contact, contact resistance and oxidation
- 3With the ignition off and the connector disconnected, use a multimeter to check that the leads to the valve have neither voltage nor contact with ground
- 4Clear the code and road test the car; if the code returns, have a workshop replace the bypass valve
Symptoms you may notice1
- No noticeable symptoms for the driver
General guidance for car owners. Diagnosis on the car can point to a different cause.