Electrical System - Signal Specifications: Overview Volvo V70 II

General information

Note. Figures shown are only examples.

HINT: For general information about CAN-troubleshooting, see

Scheme 10

1. INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. General about CAN-related diagnostic trouble codes. CEM-DF01 - DF17 can only be stored in Central electronic module (CEM). These diagnostic trouble codes are stored when an electric fault is detected in CAN-lines. Start with these diagnostic trouble codes first. CEM-1AXX only stored in Central electronic module (CEM). One diagnostic trouble code for every control module on the CAN-net. These diagnostic trouble codes indicate that Central electronic module (CEM) does not receive any reply from other control modules. XXX-E000 (HS-CAN)/E001 (LS-CAN) can be stored in all CAN-connected control modules. These diagnostic trouble codes indicate that the control module has detected interference on the CAN-net. XXX-E003 can be stored in all CAN-connected control modules except in Central electronic module (CEM). The control modules on the CAN-net listen for a message (identity number) that is sent out at regular intervals from Central electronic module (CEM). This diagnostic trouble code indicates that the control module has not received any identity number, or that the expected number is not correct. Interference on the CAN-net can also store this diagnostic trouble code. NOTE: In case of CAN-related faults, it is likely that a combination of above diagnostic trouble codes occur. 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. If a communication diagnostic trouble code can be read from the control module, the malfunction is probably intermittent. Intermittent fault in the voltage supply and ground to a control module on the CAN network results in the Central electronic module (CEM) storing a diagnostic trouble code (DTC) for an open-circuit in communication with the control module where the voltage supply does not work. There will probably not be a diagnostic trouble code (DTC) in the control module where the open-circuit in the voltage supply occurred as the control module cannot store a diagnostic trouble code (DTC) when it is not supplied with power. NOTE: Central electronic module (CEM) should not be replaced in case of CAN-fault, unless troubleshooting reveals that Central electronic module (CEM) has an internal fault. CAUTION: During this fault-tracing use the wiring diagram to provide support when taking readings.

1. Continue Refer to «Checking resistance in CAN-net»(ref-406816-S09613496342011070100000)

Scheme 11

Scheme 12

1. Ignition off
2. Disconnect the battery negative lead
3. Connect OBDII-Box (951 3015) to the diagnostics socket. HINT: Use the wiring diagram to provide support when taking readings. For general information about CAN-troubleshooting, see: INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. See «General information about fault-tracing in the CAN network»(ref-441117-S34302411522011121500000) Measure resistance between the following connections on the OBDII-box/diagnostics socket. #6 and #14. 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 HS-CAN ( ) the terminating resistors are located in Brake control module (BCM) and in Engine control module (ECM). 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. See appropriate SYSTEM WIRING DIAGRAM article. 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»(ref-406866-S10988298012011070100000) See «Contents»(ref-406811-S37635188302011070100000)

Was a fault detected?

1. YES Refer to «Verification»(ref-406816-S24535140582011070100000)
2. NO Refer to «Checking short-circuiting to ground/voltage in CAN-net»(ref-406816-S19404581752011070100000)

Scheme 13

Scheme 14

1. Connect the battery
2. Ignition on.
3. Connect OBDII-Box (951 3015) to the diagnostics socket. HINT: Use the wiring diagram to provide support when taking readings. For general information about CAN-troubleshooting, see: INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. See «General information about fault-tracing in the CAN network»(ref-441117-S34302411522011121500000) Faults in the CAN network may be due to a control module sending faulty messages that disrupt normal communication. When messages are sent incorrectly, this results in a considerable increase in the amount of traffic on the CAN network. Check the load by measuring the average voltage value on the CAN cables in relation to ground. For further information, see appropriate SYSTEM WIRING DIAGRAM article. Measure voltage between the following connections on the OBDII-box/diagnostics socket. #6 and #4 (ground). The voltage should be approx:2,8 - 3,2 V. #14 and #4 (ground). The voltage should be approx:1,8 - 2,2 V. #6 and #14. The voltage shall be between approx. 0. 55-1. 4 V. The voltage shall normally be between 0. 55 - 0. 90 V. A higher voltage may indicate increased traffic on the CAN-net. In case of fault in communication/too high traffic on the CAN-net, the voltage is considerably higher than the above stated values. 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. HINT: DiCE can be used as fault detection tool if fault is suspected on the CAN-net that cannot be detected with normal troubleshooting. Interference, intermittent faults, faulty messages on the CAN-net (chattering control modules) etc. , are examples of such faults. The tool registers fault messages used on the CAN-net. Fault messages may be caused by short intermittent malfunctions on the CAN-net or by a control module sending fault messages. See tools:951 3010 (memory card) as well as associated TJ 20402. Ignition on. Connect DiCE to the diagnostics socket. Note the blue LED-indicator. The indicator flashes to show detection of fault messages. NOTE: Certain interference may occur without any real fault Cable fault Shake the cables lightly and pull lightly on the connections during the check to locate any fault. Note the blue LED-indicator. "Chatting" control modules "Chatting" control modules may be difficult to find and troubleshooting may take time. Let the vehicle stand with DiCE connected for an extended time period. Afterwards, activate functions to provoke a malfunction. It may take up to several hours before the fault messages are sent. When the indicator starts to flash, remove the fuse for one control module at a time until the indicator stops flashing. When the indicator stops flashing, restore the fuse for the relevant control module and check that the indicator starts to flash again. Then it is likely that the problem is identified. Remedy wiring as necessary. Other information See «Battery, disconnecting»(ref-406866-S10988298012011070100000) See «Checking wiring and terminals»(ref-406811-S00386154732011070100000)

Was a fault detected?

1. YES Refer to «Identifying a control module in the CAN network»(ref-406816-S07367321352011070100000)
2. NO Refer to «Checking voltage-drop in cable for CAN-H and CAN-L, respectively»(ref-406816-S20156564712011070100000)

Note. Figures shown are only examples.

HINT: For general information about CAN-troubleshooting, see

1. INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. General about CAN-related diagnostic trouble codes. CEM-DF01 - DF17 can only be stored in Central electronic module (CEM). These diagnostic trouble codes are stored when an electric fault is detected in CAN-lines. Start with these diagnostic trouble codes first. CEM-1AXX only stored in Central electronic module (CEM). One diagnostic trouble code for every control module on the CAN-net. These diagnostic trouble codes indicate that Central electronic module (CEM) does not receive any reply from other control modules. XXX-E000 (HS-CAN)/E001 (LS-CAN) can be stored in all CAN-connected control modules. These diagnostic trouble codes indicate that the control module has detected interference on the CAN-net. XXX-E003 can be stored in all CAN-connected control modules except in Central electronic module (CEM). The control modules on the CAN-net listen for a message (identity number) that is sent out at regular intervals from Central electronic module (CEM). This diagnostic trouble code indicates that the control module has not received any identity number, or that the expected number is not correct. Interference on the CAN-net can also store this diagnostic trouble code. NOTE: In case of CAN-related faults, it is likely that a combination of above diagnostic trouble codes occur. 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. If a communication diagnostic trouble code can be read from the control module, the malfunction is probably intermittent. Intermittent fault in the voltage supply and ground to a control module on the CAN network results in the Central electronic module (CEM) storing a diagnostic trouble code (DTC) for an open-circuit in communication with the control module where the voltage supply does not work. There will probably not be a diagnostic trouble code (DTC) in the control module where the open-circuit in the voltage supply occurred as the control module cannot store a diagnostic trouble code (DTC) when it is not supplied with power. NOTE: Central electronic module (CEM) should not be replaced in case of CAN-fault, unless troubleshooting reveals that Central electronic module (CEM) has an internal fault. CAUTION: During this fault-tracing use the wiring diagram to provide support when taking readings.

1. Continue Refer to «Checking resistance in CAN-net»(ref-406816-S29346666612011070100000)

Note. Figures shown are only examples.

HINT: For general information about CAN-troubleshooting, see

1. INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. General about CAN-related diagnostic trouble codes. CEM-DF01 - DF17 can only be stored in Central electronic module (CEM). These diagnostic trouble codes are stored when an electric fault is detected in CAN-lines. Start with these diagnostic trouble codes first. CEM-1AXX only stored in Central electronic module (CEM). One diagnostic trouble code for every control module on the CAN-net. These diagnostic trouble codes indicate that Central electronic module (CEM) does not receive any reply from other control modules. XXX-E000 (HS-CAN)/E001 (LS-CAN) can be stored in all CAN-connected control modules. These diagnostic trouble codes indicate that the control module has detected interference on the CAN-net. XXX-E003 can be stored in all CAN-connected control modules except in Central electronic module (CEM). The control modules on the CAN-net listen for a message (identity number) that is sent out at regular intervals from Central electronic module (CEM). This diagnostic trouble code indicates that the control module has not received any identity number, or that the expected number is not correct. Interference on the CAN-net can also store this diagnostic trouble code. NOTE: In case of CAN-related faults, it is likely that a combination of above diagnostic trouble codes occur. 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. If a communication diagnostic trouble code can be read from the control module, the malfunction is probably intermittent. Intermittent fault in the voltage supply and ground to a control module on the CAN network results in the Central electronic module (CEM) storing a diagnostic trouble code (DTC) for an open-circuit in communication with the control module where the voltage supply does not work. There will probably not be a diagnostic trouble code (DTC) in the control module where the open-circuit in the voltage supply occurred as the control module cannot store a diagnostic trouble code (DTC) when it is not supplied with power. NOTE: Central electronic module (CEM) should not be replaced in case of CAN-fault, unless troubleshooting reveals that Central electronic module (CEM) has an internal fault. CAUTION: During this fault-tracing use the wiring diagram to provide support when taking readings.

1. Continue Refer to «Checking resistance in CAN-net»(ref-406816-S26015037872011070100000)

Note. Figures shown are only examples.

HINT: For general information about CAN-troubleshooting, see

1. INFORMATION/PRODUCTSPECIFICATIONS/Design and function/37/CAN-net. General about CAN-related diagnostic trouble codes. CEM-DF01 - DF17 can only be stored in Central electronic module (CEM). These diagnostic trouble codes are stored when an electric fault is detected in CAN-lines. Start with these diagnostic trouble codes first. CEM-1AXX only stored in Central electronic module (CEM). One diagnostic trouble code for every control module on the CAN-net. These diagnostic trouble codes indicate that Central electronic module (CEM) does not receive any reply from other control modules. XXX-E000 (HS-CAN)/E001 (LS-CAN) can be stored in all CAN-connected control modules. These diagnostic trouble codes indicate that the control module has detected interference on the CAN-net. XXX-E003 can be stored in all CAN-connected control modules except in Central electronic module (CEM). The control modules on the CAN-net listen for a message (identity number) that is sent out at regular intervals from Central electronic module (CEM). This diagnostic trouble code indicates that the control module has not received any identity number, or that the expected number is not correct. Interference on the CAN-net can also store this diagnostic trouble code. NOTE: In case of CAN-related faults, it is likely that a combination of above diagnostic trouble codes occur. 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. If a communication diagnostic trouble code can be read from the control module, the malfunction is probably intermittent. Intermittent fault in the voltage supply and ground to a control module on the CAN network results in the Central electronic module (CEM) storing a diagnostic trouble code (DTC) for an open-circuit in communication with the control module where the voltage supply does not work. There will probably not be a diagnostic trouble code (DTC) in the control module where the open-circuit in the voltage supply occurred as the control module cannot store a diagnostic trouble code (DTC) when it is not supplied with power. NOTE: Central electronic module (CEM) should not be replaced in case of CAN-fault, unless troubleshooting reveals that Central electronic module (CEM) has an internal fault. CAUTION: During this fault-tracing use the wiring diagram to provide support when taking readings.

1. Continue Refer to «Checking resistance in CAN-net»(ref-406816-S24481511382011070100000)