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Home >> Volvo >> 1998 >> C70 Convertible L5-2.4L Turbo VIN 56 B5254T >> Repair and Diagnosis >> Brakes and Traction Control >> Antilock Brakes / Traction Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Check The TRACS Circuit Closing Switch >> Checking TRACS Switch Circuit

Checking TRACS Switch Circuit






Checking TRACS switch circuit

Checking activation with TRACS switch




- Ignition on.
- Press in hold down the TRACS switch.
Check that the TRACS warning lamp lights.





Is warning lamp lit?

Yes - Connecting breakout box and checking ground terminals

No - Checking signal to TRACS switch

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Checking signal to TRACS switch




- Ignition off.
- Remove TRACS switch and disconnect.
- Ignition on.
Connect a voltmeter between TRACS switch connector terminal 1 and ground.





The voltmeter should read approximately battery voltage.

OK - Checking ground lead to TRACS switch

Not OK - Checking the signal cable

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Checking the signal cable




- Ignition off.
- Expose the combined instrument panel.
Connect an ohmmeter between TRACS switch connector terminal 1 and combined instrument panel terminal A29.





The ohmmeter should read approximately 0 ohms.

OK - Checking the bulb

Not OK - Checking for an open-circuit in the cable

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Checking the bulb
Check that the bulb in the combined instrument panel is intact.





Is the bulb intact?

Yes - Replacing component

No - Replacing component

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Replacing component
Try a new combined instrument panel.





Select "Continue" when the component has been replaced.

Continue - Verification

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Replacing component
Replace bulb.





Select "Continue" when the component has been replaced.

Continue - Verification

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Checking for an open-circuit in the cable
Check cable between combined instrument panel terminal A29 and TRACS switch connector terminal 1 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Select "Continue" when the fault has been repaired.

Continue - Verification

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Checking ground lead to TRACS switch




- Ignition off.
- TRACS switch disconnected.
Connect an ohmmeter between TRACS switch connector terminal 5 and ground





The ohmmeter should read approximately 0 ohms.

OK - Replacing component

Not OK - Checking for an open-circuit in the cable

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Replacing component
Try a new TRACS switch.

Select "Continue" when the component has been replaced.

Continue - Verification

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Checking for an open-circuit in the cable
Check cable between TRACS switch terminal 5 and ground terminal 31/50 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Select "Continue" when the fault has been repaired.

Continue - Verification

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Connecting breakout box and checking ground terminals





Connecting the breakout box

Connecting the breakout box




- Ignition off.
- Disconnect the ABS control module by pressing in the catch on the rear edge of the cover (wheel arch side). Carefully turn the cover upwards so that the locking catches release.
- Check control module and control module connector to ensure that: Male and female terminals are undamaged and properly attached (cannot be pressed in). Female terminal cables are correctly connected to the terminals.
- Pay particular attention to the terminals related to the diagnostic trouble code (DTC)/symptom.
- Connect adapter 951 1354 Adapter 25-pin ABS 850 951 1354 Adapter 25-Pin ABS 850 to the control module connector (wiring side) and connect breakout box 951 1428 Breakout box 951 1428 Breakout Box to the adapter.
- Control module disconnected.
- Then check ground terminals.






Continue - Checking ground terminals

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Checking ground terminals








- Ignition off.
- Switch off all equipment that takes power from the battery (courtesy lighting, radio etc).




- Connect an ohmmeter between battery negative terminal and #8 and #24 on the breakout box.

The ohmmeter should read approximately 0 ohms for all readings.

OK - Return to the fault-tracing procedure where it was interrupted.
Reading is OK

Not OK - Check ground terminal 1/1 (battery negative terminal) and cable between ground terminal and control module #8 and #24, for an open-circuit and contact resistance.-Return to the fault-tracing procedure where it was interrupted.
Value is not OK

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Reading is OK
- Return to the fault-tracing procedure where it was interrupted.

Continue - FAULT FOUND

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Value is not OK
- Check ground terminal 1/1 (battery negative terminal) and cable between ground terminal and control module #8 and #24, for an open-circuit and contact resistance.
- Return to the fault-tracing procedure where it was interrupted.

Continue - FAULT FOUND

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FAULT FOUND - Checking signal to control module

FAULT-TRACING FAILED - Checking signal to control module

No Fault Found - Checking signal to control module

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Checking signal to control module








- Ignition off.
- Control module disconnected.
- Ignition on.
Connect a voltmeter between #15 and #8 on the breakout box.









The voltmeter should read approximately battery voltage.

OK - Fault cause and checking for contact resistance and oxidation

Not OK - Checking for an open-circuit in the cable

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Fault cause and checking for contact resistance and oxidation
The diagnostic trouble code (DTC) was set because of poor contact in the transmission control module (TCM) connector.
Check control module connector for contact resistance and oxidation and remedy according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.

Select "Continue" when the fault has been repaired.

Continue - Verification

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Checking for an open-circuit in the cable
Check cable between TRACS switch connector terminal 1 and control module #15 for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Select "Continue" when the fault has been repaired.

Continue - Verification

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Verification

Hint: After carrying out the repair check that the fault has been remedied.




- Ignition off.
- Reconnect connectors, reinstall components.
- Ignition on.
When the ignition is switched on the control module lights the TRACS warning lamp which should go out again after approximately 2 seconds.

Note! The warning lamp will not go out if a fault has been stored in the control module.

Press in and hold down the TRACS switch. Check that the TRACS warning lamp lights.





Is warning lamp lit?

Yes - FAULT FOUND

No - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should be diagnosed and remedied. Since this is not the case the fault-tracing process has failed.
Complete the fault-tracing for those fault or try again.

Do you want to terminate fault-tracing at this time?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking activation with TRACS switch

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