Checking Communication

Checking Power Supply
- Ignition ON.
- Volvo Scan Tool (ST) connected to data link connector (DLC).
- Power up the Volvo Scan Tool.
- Check that the display lights.
- Does the Volvo Scan Tool display light?

Yes:
- Proceed to: Checking Ground Terminals section below.

No:
- Proceed to: Checking Data Link Connector Power Supply section below.





Checking Data Link Connector Power Supply
- Ignition OFF.
- Disconnect the Volvo Scan Tool.
- Disconnect the data link connector.
- Connect a voltmeter between data link connector terminal 16 and ground.
- The voltmeter should read battery voltage.

If reading is OK:
- Proceed to: Checking Data Link Connector Power Ground section below.

If reading is incorrect:
- Proceed to: Checking Fuse 14 section below.





Checking Fuse 14
- Check that fuse 14 is intact.
- Is the fuse intact?

Yes:
- Proceed to: Checking Voltage Before the Fuse section below.

No:
- Proceed to: Checking for Short-circuit to Ground section below.





Checking for Short-circuit to Ground
- Check cable between data link connector terminal 16 and fuse 14 for a short-circuit to ground.
- Proceed to: Verification section below.





Checking Voltage Before the Fuse
- Ignition OFF.
- Connect a voltmeter between the rear socket of the fuse holder to fuse 14 and ground.
- The voltmeter should read battery voltage.

If reading is OK:
- Proceed to: Checking for an Open-circuit section below.

If reading is incorrect:
- Proceed to: Checking for an Open-circuit 2 sections below.





Checking for an Open-circuit
- Check cable between fuse 14 and data link connector terminal 16 for an open-circuit.
- Proceed to: Verification section below.





Checking for an Open-circuit
- Check the cable between fuse 14 and battery positive terminal for an open-circuit.
- Proceed to: Verification section below.





Checking Data Link Connector Power Ground
- Ignition OFF.
- Connect ohmmeter between data link connector terminal 4 and ground.
- The ohmmeter should read approx. 0 Ohms.

If reading is OK:
- Proceed to: Checking Data Link Connector Signal Ground section below.

If reading is incorrect:
- Proceed to: Checking for an Open-circuit section below.





Checking for an Open-circuit
- Check cable between data link connector terminal 4 and ground terminal (31/67) by the right-hand seat support for an open-circuit.
- Proceed to: Verification section below.





Checking Data Link Connector Signal Ground
- Ignition OFF.
- Connect ohmmeter between data link connector terminal 5 and ground.
- The ohmmeter should read approx. 0 Ohms.

If reading is OK:
- Proceed to: Checking Voltage to Adapter Box section below.

If reading is incorrect:
- Proceed to: Checking for an Open-circuit section below.





Checking for an Open-circuit
- Check cable between data link connector terminal 4 and ground terminal (31/53) by the left side member for an open-circuit.
- Proceed to: Verification section below.





Checking Voltage to Adapter Box
- Ignition ON.
- Volvo Scan Tool connected to data link connector.
- Separate Scan Tool wiring at the adapter box.
- Connect a voltmeter between ground and the 25-pin connector terminal:

- 15 (measured to data link connector)
- 20 (measured to data link connector)
- 21 (measured to data link connector)
- 22 (measured to data link connector)

- The voltmeter should read battery voltage for all readings.

If reading is OK:
- Proceed to: Checking Power Ground to Adapter Box section below.

If reading is incorrect:
- Proceed to: Replacing Wiring section below.

Replacing Wiring
- Try with new Scan Tool wiring.
- Proceed to: Verification section below.





Checking Power Ground to Adapter Box
- Ignition OFF.
- Connect Scan Tool wiring to data link connector.
- Disconnect Scan Tool wiring from adapter box.
- Connect an ohmmeter between ground and the 25-pin connector terminal:

- 23 (measured to data link connector)
- 24 (measured to data link connector)
- 25 (measured to data link connector)

- The ohmmeter should read 0 Ohms for all readings.

If reading is OK:
- Proceed to: Checking Signal Ground to Adapter Box section below.

If reading is incorrect:
- Proceed to: Replacing Wiring section above.





Checking Signal Ground to Adapter Box
- Ignition OFF.
- Connect Scan Tool wiring to data link connector.
- Disconnect Scan Tool wiring from adapter box.
- Connect an ohmmeter between the 2-pin connector terminal 14 (data link connector side) and ground.
- The ohmmeter should read 0 Ohms.

If reading is OK:
- Proceed to: Checking Supply Voltage to Volvo Scan Tool section below.

If reading is incorrect:
- Proceed to: Replacing Wiring section above.





Checking Supply Voltage to Volvo Scan Tool
- Ignition ON.
- Connect Scan Tool wiring to data link connector.
- Connect Scan Tool to adapter box.
- Disconnect the 3-pin connector from the Scan Tool.
- Check that the switch on the adapter box is on.
- Connect a voltmeter between ground and the 3-pin connector terminal:

- 1 (measured to data link connector)
- 3 (measured to data link connector)

- The voltmeter should read:

- Terminal 1 and ground: 7-9 V.
- Terminal 3 and ground: battery voltage.

If reading is OK:
- Proceed to: Checking Volvo Scan Tool Ground section below.

If reading is incorrect:
- Proceed to: Replacing Component section below.

Replacing Component
- Try a new adapter box.
- Proceed to: Verification section below.





Checking Volvo Scan Tool Ground
- Ignition OFF.
- Connect Scan Tool wiring to data link connector.
- Disconnect the 3-pin connector from the Scan Tool.
- Connect an ohmmeter between the 3-pin connector terminal 2 (data link connector side) and ground.
- The ohmmeter should read 0 Ohms.

If reading is OK:
- Proceed to: Replacing Component section below.

If reading is incorrect:
- Proceed to: Replacing Component section above.





Replacing Component
- Try a new Volvo Scan Tool.
- Proceed to: Verification section below.





Checking Ground Terminals
- Ignition OFF.
- Connect the test box and check ground terminals.
- The ohmmeter should read approx. 0 Ohms for all readings.

If reading is OK:
- Proceed to: Checking Supply Voltage (15 supply) section below.

If reading is incorrect:
- Proceed to: Fault-tracing Information section below.

Fault-tracing Information
- The cause of the fault has been a poor ground terminal.
- Proceed to: Verification section below.





Checking Supply Voltage (15 supply)
- Ignition ON.
- Transmission control module (TCM) connected.
- Connect a voltmeter between # 29 and # 1 on the test box.
- The voltmeter should read approx. battery voltage.

If reading is OK:
- Proceed to: Checking Communication Cable to the Data Link Connector section below.

If reading is incorrect:
- Proceed to: Checking Fuse 11B/6 section below.





Checking Fuse 11B/6
- Check that fuse 11B/6 is intact.
- Is the fuse intact?

Yes:
- Proceed to: Checking for an Open-circuit section below.

No:
- Proceed to: Checking for Short-circuit to Ground section below.





Checking for an Open-circuit
- Check cable between transmission control module # 29 and main relay 2/32 for an open-circuit.
- Proceed to: Verification section below.





Checking for Short-circuit to Ground
- Check cable between transmission control module # A29 and fuse 11B/6 for short-circuit to ground.
- Replace fuse 1/11.
- Proceed to: Verification section below.





Checking Communication with the Engine Control Module
- Ignition ON.
- Volvo Scan Tool connected to data link connector.
- Try to establish communication with the Motronic 4.4 engine control module.
- Is communication established?

Yes:
- Proceed to: Checking for an Open-circuit section below.

No:
- Proceed to: Checking Communication Cable to the Data Link Connector section below.





Checking for an Open-circuit
- Check the cable between data link connector terminal 7 and transmission control module # 21 for an open-circuit.
- Proceed to: Verification section below.





Checking Communication Cable to the Data Link Connector
- Ignition OFF.
- Disconnect the Scan Tool from the data link connector.
- Connect an ohmmeter between the DLC connector terminals 7 and Test box terminal # 21.
- The ohmmeter should read 0 Ohms.

If reading is OK:
- Proceed to: Checking the Communication Cable section below.

If reading is incorrect:
- Proceed to: Checking for an Open-circuit section below.





Checking for an Open-circuit
- Check the cable between data link connector terminal 7 and transmission control module # 21 for an open-circuit.
- Proceed to: Verification section below.





Checking the Communication Cable
- Ignition OFF.
- Connect the transmission control module.
- Ignition ON.
- Connect a voltmeter between data link connector terminal 7 and ground.
- The voltmeter should read approx. 9-11 V.

If reading is OK:
- Proceed to: Checking Communication Cable to Adapter Box section below.

If value is lower:
- Proceed to: Checking for Short-circuit to Ground section below.

If value is higher:
- Proceed to: Checking for a Short-circuit to Supply Voltage section below.





Checking for Short-circuit to Ground
- Check cable between data link connector terminal 7 and control modules connected to this cable for a short-circuit to ground.
- Proceed to: Verification section below.





Checking for a Short-circuit to Supply Voltage
- Check the cable between data link connector terminal 7 and the control modules connected to this cable for a short-circuit to supply voltage.
- Proceed to: Verification section below.





Checking Communication Cable to Adapter Box
- Ignition ON.
- Connect Scan Tool wiring to data link connector.
- Separate Scan Tool wiring at the adapter box.
- Connect an ohmmeter between the 2-pin connector terminal 5 (data link connector side) and ground.
- The voltmeter should read approx. 9-11 V.

If reading is OK:
- Proceed to: Checking Communication with the Volvo Scan Tool section below.

If reading is incorrect:
- Proceed to: Checking Power Supply section above.





Checking Communication with the Volvo Scan Tool
- Connect Scan Tool wiring to data link connector.
- Connect Scan Tool wiring to adapter box.
- Disconnect the 62-pin connector from the Scan Tool.
- Ignition ON.
- Check that the switch on the adapter box is on.
- Connect a voltmeter between the 62-pin connector terminal 47 (Scan Tool side) and ground.
- Try to establish communications with the transmission control module.
- Voltage should be approx. 8.6 V. It should then start to fluctuate rapidly between 8.6 V and 0 V when the Scan Tool tries to establish communication.

If reading is OK:
- Proceed to: Replacing Component 2 sections above.

If reading is incorrect:
- Proceed to: Replacing Component 1 section above.





Verification
- Ignition OFF.
- Reconnect connectors, reinstall components etc.
- Volvo Scan Tool connected to data link connector.
- Try to establish communication with the transmission control module.
- Has communication been established with the transmission control module.

Yes:
- Fault corrected.

No:
- Proceed to: Information section below.

Information
The verification result shows that the fault persists.

- Do you want to exit fault-tracing?

Yes:
- Fault not corrected.

No:
- Proceed to: Checking Power Supply section above.