Checking Control Panel
YA. Fault-tracing informationCondition
No diagnostic trouble codes (DTCs)
The fault is permanent.
Possible source
- Open-circuit on wiring between control panel and control module.
- Contact resistance in terminals.
- Loose contacts in terminals.
- Defective control panel.
- Defective control module.
Fault symptom(s)
- Seat will not move forward/backward.
- Seat will not adjust height.
- No backrest angle adjustment.
- Memory activation does not work
- Fault-tracing begins at YB.
YB. Checking control panel
YB1: Checking the control buttons status
- Ignition OFF.
- Select scrolling values.
Activate the seat functions in both directions using the control buttons and read off the status for each button.
Activate the tour memory buttons and read off the status. Volvo Scan Tool (ST) Scrolling values, Other Parameter Tables
The status for each function should change from NOT ACTIVE to ACTIVE when the seat is operated.
If reading is OK:
- Fault not found
If reading is incorrect:
- YB2
YB2: Checking, contact resistance and oxidation
- Ignition OFF.
- Disconnect 10-pin connector B.
- Check and correct the 16-pin connector B for loose contact and contact resistance and oxidation.
Then continue with:
- YB3
YB3: Connecting the break-out box
- Ignition OFF.
- Connect break-out box to 16-pin connector. Connecting the break-out box, Connecting The Break-out Box
Then continue with:
- YB4
YB4: Checking control buttons
- Ignition OFF.
- Connect an ohmmeter between the break-out box socket to the appropriate button and ground (socket 36), Connector D Signal Tables
- The ohmmeter should read 0 ohm when the respective buttons are pressed.
If reading is OK:
- YB6
If reading is incorrect:
- YB5
YB5: Checking for an open-circuit
Check leads between control panel and control module for open-circuit.
If a fault is detected, try a new control panel. Control panel replacement Service and Repair
Then continue with:
- YB9
YB6: Checking the control module
- Ignition OFF.
- Connect up seat in car. Wiring up for voltage measurement Wiring Up For Voltage Measurement
Select scrolling values.
Activate the seat functions in both directions using the control buttons and read off the status for each button.
Activate the four memory buttons and read off the status. Volvo Scan Tool (ST) Scrolling values Other Parameter Tables
The status for each function should change from NOT ACTIVE to ACTIVE when the seat is operated.
If reading is OK:
- YB8
If reading is incorrect:
- YB7
YB7: Replace component
Try a new control module. Control module, Service and Repair
Then continue with:
- YB9
YB8: Fault-tracing information
No faults detected on the control panel. The fault is probably due to contact resistance in the terminals.
Then continue with:
- Fault corrected
YB9: Verification
Hint: After carrying out the repair, check that the fault has been remedied as follows:
- Ignition OFF.
- Reinstall components, connectors etc.
- Connect up seat in car. Wiring up for voltage measurement Wiring Up For Voltage Measurement
- Select scrolling values.
- Activate the seat functions in both directions using the control buttons and read off the status for each button.
- Activate the four memory buttons and read off the status.
- The status for the defective button should change from NOT ACTIVE to ACTIVE when activated.
If reading is OK:
- Fault corrected
If reading is incorrect:
- YB10
YB10: Fault-tracing information
The fault should now have been diagnosed and corrected. Since this is not the case the fault-tracing has failed.
Do you want to exit fault-tracing?
Yes:
- Fault not corrected
No:
- YB1