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Home >> Volvo >> 1998 >> S70 GLT L5-2.4L Turbo VIN 56 B5254T >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> Manufacturer Code Charts >> AT / DTC Codes (Transmission Control Module) >> AT-232 Speedometer Signal >> Signal Missing

Signal Missing






SPECIAL TOOLS
Test box tool No. 981 3190, or equivalent
Volvo scan tool No. 998 8686, or equivalent

SIGNAL MISSING
1. Checking vehicle speed signal

NOTE: An alternative to the following method is to drive the car on the road.

- Preparation:
Ignition OFF
Raise car so that front wheels rotate freely.
Engine idling.
Select scrolling values.
Read off speed.
Move the gear selector to position D so the front wheels begin to rotate.
- Check that speed increases with engine speed (RPM).

NOTE:
- When the rear wheels are stationary and the front wheels rotate Diagnostic Trouble Codes (DTCs) may can be stored in the ABS system.
- Erase any DTCs stored in the ABS system after fault-tracing.
- Refer to Brakes and Traction Control.
- Ensure that the front wheels are not rotating when the gear shift lever is moved.
- Does speed increase with engine speed (RPM)?

YES: Proceed to step 19
NO: Proceed to step 2





2. Connecting the test box
- Preparation:
Ignition OFF
- Connect the test box and check ground terminals. Connecting the Test Box
- Then continue with step 3





3. Checking Vehicle Speed Sensor (VSS) circuit.
- Preparation:
Ignition OFF
Transmission Control Module (TCM) disconnected.
- Connect an ohmmeter between #11 (#A11) and #12 (#A12) on the test box.
- The ohmmeter should read 300-600 Ohms
- If reading is OK:
Proceed to step 13
- If reading is incorrect:
Proceed to step 4





4. Checking VSS resistance
- Preparation:
Ignition OFF
Remove the Air Cleaner (ACL) housing to access the VSS connector.
Disconnect the VSS connector.
- Connect an ohmmeter between VSS connector terminals 1 and 2 (VSS side)
- The ohmmeter should read approximately 300-600 Ohms
- If reading is OK:
Proceed to step 6
- If reading is incorrect:
Proceed to step 5





5. Replacing component
- Preparation:
Ignition OFF
- Try a new VSS, refer to Powertrain Management.
- Then continue with step 17





6. Checking resistance in signal (+) cable
- Preparation:
Ignition OFF
VSS disconnected.
- Connect an ohmmeter between VSS connector terminals 1 and #11 (#A11) on the test box.
- The ohmmeter should read approx. 0 Ohms
- If reading is OK:
Proceed to step8
- If reading is incorrect:
Proceed to step7





7. Checking for an open-circuit
- Check cable between VSS connector terminal 1 and TCM #All for an open-circuit according to step 2 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





8. Checking resistance in signal (-) cable
- Preparation:
Ignition OFF
VSS disconnected.
- Connect an ohmmeter between VSS connector terminals 2 and #12 (#A12) on the test box.
- The ohmmeter should read approx. 0 Ohms
- If reading is OK:
Proceed to step 10
- If reading is incorrect:
Proceed to step 9





9. Checking for an open-circuit
- Check cable between VSS connector terminal 2 and TCM terminal #A12 for an open-circuit according to step 2 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





10. Checking signal cable resistance
- Preparation:
Ignition OFF
VSS disconnected.
TCM disconnected.
- Connect an ohmmeter between #11 (#A11) and #12 (#A12) on the test box.
- The ohmmeter should read infinite resistance
- If reading is OK:
Proceed to step 11
- If reading is incorrect:
Proceed to step 12





11. Checking for contact resistance and oxidation.
- Preparation:
Ignition OFF
- The DTC was caused by poor contact in TCM and VSS connectors.
- Check connectors for contact resistance and oxidation and remedy according to step 5 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





12. Checking for a short-circuit
- Check cable between VSS connector terminal 1 and TCM #All and cable between terminal 2 and TCM #A12 for a short-circuit to each other.
- Then continue with step 17





13. Checking signal cables
- Preparation:
Ignition OFF
Test box connected
Connect TCM
Ignition ON
- Connect a voltmeter between #11 (#A11) and #12 (#A12) on the test box.
- The voltmeter should read approx. 2.5 volts
- If reading is OK:
Proceed to step 14
- If value is lower:
Proceed to step 15
- If value is higher:
Proceed to step 16





14. Checking for contact resistance and oxidation.
- Preparation
Ignition OFF
- The DTC was caused by poor contact in the TCM connector
- Check transmission and control module connectors for contact resistance and oxidation and remedy according to step 5 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





15. Checking for a short-circuit
- Check cables between VSS and TCM #All and #A12 for a short-circuit to ground according to step 3 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





16. Checking for a short-circuit
- Check cables between VSS and TCM #All and #A12 for a short-circuit to supply voltage according to step 4 of checking for permanent faults. Checking For Permanent Faults
- Then continue with step 17





17. Verification
- After carrying out the repair, check that the fault has been remedied as follows

NOTE: An alternative to the following method is to drive the car on the road.

- Preparation:
Ignition OFF
Reconnect connectors, reinstall components etc.
Raise car so that front wheels rotate freely.
Engine idling
- Check that speed increases with engine speed (RPM).

NOTE:
- When the rear wheels are stationary and the front wheels rotate DTCs may can be stored in the ABS system.
- Erase any DTCs stored in the ABS system after fault-tracing.
- Refer to Brakes and Traction Control
- Ensure that the front wheels are not rotating when the gear shift lever is moved.
- Does speed increase with engine speed (RPM)?
YES: Fault corrected
NO: Proceed to step 18
18. Fault-tracing information
- The verification result shows that the fault persists.
- Do you want to exit fault-tracing?
YES: Fault not corrected
NO: Proceed to step 1





19. Intermittent fault
- Preparation:
Ignition OFF
- Check VSS and TCM connectors for contact resistance and oxidation according to step 6 of checking for intermittent faults. Checking For Intermittent Faults
- Check cables between VSS and TCM #All and #A12 for:
An intermittent open-circuit according to step 2 of checking for intermittent faults. Checking For Intermittent Faults
An intermittent short-circuit to ground according to step 3 of checking for intermittent faults. Checking For Intermittent Faults
An intermittent short-circuit to supply voltage according to step 4 of checking for intermittent faults. Checking For Intermittent Faults
An intermittent short-circuit to each other.
- Then continue with step 20
20. Fault-tracing information
- For intermittent faults fault-tracing is not followed by a verification because the fault is not present at this moment.
- Do you want to repeat fault-tracing?
YES: Proceed to step 1
NO: Operation done


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