VOLVO
CEM-B10E901 - Engine Hood Ajar Switch #2. General Failure Information. General electrical failure
System
Central Electronic Module (CEM)
Volvo models this fault code applies to
Applies to the following models:
7 modelsS60 (2011–), S80 (2007–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The bonnet switch has two wires that feed two separate CEM inputs. The CEM reads the bonnet position by which input is grounded: one input is grounded only with the hood raised and the other only with it lowered. The code is stored when both inputs are grounded or when neither is. Engine Remote Start (ERS) and the alarm then cannot be activated, and no visible warning is shown.
Possible causes
- Poor contact and oxidation in the contact pieces
- One of the wires from the bonnet switch has been shorted to ground
- A break in one of the wires from the bonnet switch
- The two wires from the bonnet switch have shorted together
- The bonnet switch is damaged
What you can do
- 1Check that the bonnet closes properly and that nothing is in the way of the switch
- 2Check that the relevant fuses are intact. Their locations are in the owner's manual or on the fuse box cover
- 3Look for chafing and loose connectors in the wiring to the bonnet switch
- 4Use a multimeter to check that none of the wires from the bonnet switch have contact with ground (the body) or with each other
- 5If you have a diagnostic tool: check whether the bonnet position appears in live data and changes when the bonnet is opened and closed
- 6If the fault returns, have a workshop with diagnostic equipment check the bonnet switch and the control module
Symptoms you may notice2
- Engine Remote Start (ERS) does not work
- The alarm cannot be armed and no visible indication is shown
General guidance for car owners. Diagnosis on the car can point to a different cause.