Volvo C30 2007 Service And Repair Manual page 311

Connect OBDII-Box (951 3015) to the diagnostics socket.

For general information about CAN-troubleshooting:
see GENERAL INFORMATION ABOUT FAULT-TRACING IN THE CAN NETWORK

Measure resistance between the following connections on the OBDII-box/diagnostics socket.
#3 and #11. The resistance should be approx. 55 - 65 ohms.

If resistance is approx. 120 ohms, this indicates open circuit in the circuit so that only one

terminating resistor (120 ohms) has been measured.
If resistance is above 1 kohms this indicates open circuit/high contact resistance somewhere in the

circuit.
If resistance is below 55 ohms this indicates short-circuiting/contact resistance between the CAN-

lines somewhere in the circuit.
HINT: For LS-CAN , terminating resistors are located in Driver information module (DIM) and in
Supplemental restraint system module (SRS).
Twist the cable harness and wiggle connectors where they can be accessed along the cable harness during
every measurement, and note if the resistance changes to detect intermittent short-circuits or open circuit.
NOTE: Resistance measurement measures only main lines in the CAN-net (in
circuit where both terminating resistors are found), not branches to certain
control modules. Open circuit on branching without a terminating resistor
cannot be detected with this measurement. However, short-circuiting on a
branch can be detected. To measure resistance in the CAN-net to control
modules located in a branching of their own, the measurement shall be
done against the CAN-net at that control module. The values shall be as
above.
NOTE: After fault with control modules that interfere with communication, other
control modules may remain in Limp-Home (that is, they work with
reduced functionality) even when the ignition has been turned off and on a
few times. For certain faults in the CAN-net where control modules have
stopped communicating, it may help to disconnect/reconnect the battery
to "restart" the control module/CAN-net.
Remedy wiring as necessary.
Other information
see BATTERY, DISCONNECTING

see CHECKING WIRING AND TERMINALS

2012 Volvo C30 T-5
ELECTRICAL Body Electrical