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Home >> Volvo >> 1998 >> S90 L6-2.9L VIN 96 B6304S >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> Manufacturer Code Charts >> AT / DTC Codes (Transmission Control Module) >> AT-313 Gear-Shift Position Sensor >> Faulty Signal

Faulty Signal





Checking Gear-shift Position Sensor
- Ignition ON.
- Go into scrolling values.
- Read gear-shift position sensor position.
- Move the gear selector to all shift positions a number of times, and repeatedly select the same position to check the operation of the gear-shift position sensor.
- Are all values OK?

Yes:
- Proceed to: Intermittent Fault section below.

No:
- Proceed to: Checking Gear-shift Position Sensor Adjustment section below.





Checking Gear-shift Position Sensor Adjustment
- Ignition OFF.
- Check that the gear-shift position sensor is correctly adjusted.
- Is the gear-shift position sensor correctly adjusted?

Yes:
- Proceed to: Checking Gear-shift Position Sensor Ground Terminal section below.

No:
- Proceed to: Adjusting Component section below.

Adjusting Component
- Adjust gear-shift position sensor.
- Proceed to: Verification section below.





Checking Gear-shift Position Sensor Ground Terminal
- Ignition OFF.
- Connect an ohmmeter between gear-shift position sensor casing and transmission housing.

NOTE: The gear-shift position sensor is grounded via its two retaining screws and its mating surface with the transmission.

- The ohmmeter should read approx. 0 Ohms.

If reading is OK:
- Proceed to: Connecting The Test Box section below.

If reading is incorrect:
- Proceed to: Remedying Gear-shift Position Sensor Ground Terminal section below.

Remedying Gear-shift Position Sensor Ground Terminal
- Remedy gear-shift position sensor ground terminal. Check gear-shift position sensor adjustment after corrective action.
- Proceed to: Verification section below.





Connecting The Test Box
- Ignition OFF.
- Connect the test box and check ground terminals.
- Proceed to: Checking Signal Cable Resistance To Ground section below.





Checking Signal Cable Resistance To Ground
- Ignition OFF.
- Test box connected.
- Disconnect transmission connector C.
- Transmission control module (TCM) disconnected.
- Connect an ohmmeter between test box # 15 and 27 "A", # 41 "B, # 26 "C", # 13 "PA"
- The ohmmeter should read infinite resistance.

If reading is OK:
- Proceed to: Checking Signal Cable Resistance section below.

If reading is incorrect:
- Proceed to: Checking For Short-circuit To Ground section below.





Checking For Short-circuit To Ground
- Check cable between transmission connector C (transmission control module side) terminal:

- 5 and transmission control module # 27 "A"
- 6 and transmission control module # 41 "B"
- 7 and transmission control module # 26 "C"
- 8 and transmission control module # 13 "PA"

- Check for short-circuits to ground.
- Proceed to: Verification section below.





Checking Signal Cable Resistance
- Ignition OFF.
- Transmission connector C disconnected.
- Connect an ohmmeter between transmission connector C (transmission control module side) terminal:

- 5 and test box # 27 "A"
- 6 and test box # 41 "B"
- 7 and test box # 26 "C"
- 8 and test box # 13 "PA"

- The ohmmeter should read approx. 0 Ohms for all readings.

If reading is OK:
- Proceed to: Checking For Short-circuit To Supply Voltage In Signal Cable section below.

If reading is incorrect:
- Proceed to: Checking For An Open-circuit section below.





Checking For An Open-circuit
- Check cable between transmission connector C terminal:

- 5 and transmission control module # 27 "A"
- 6 and transmission control module # 41 "B"
- 7 and transmission control module # 26 "C"
- 8 and transmission control module # 13 "PA"

- Check for open-circuits.
- Proceed to: Verification section below.





Checking For Short-circuit To Supply Voltage In Signal Cable
- Ignition OFF.
- Connect transmission control module.
- Ignition ON.
- Connect an electrician's screwdriver (bulb at least 3W) between test box # 15 and # 27 "A", # 41 "B", # 26 "C", # 13 "PA".
- The bulb should not light. If the lamp lights there is probably a short-circuit to supply voltage in the circuit.
- Is the bulb out?

Yes:
- Proceed to: Checking Gear-shift Position Sensor Operation section below.

No:
- Proceed to: Checking For A Short-circuit To Supply Voltage section below.





Checking For A Short-circuit To Supply Voltage
- Check cable between transmission connector C terminal:

- 5 and transmission control module # 27 "A"
- 6 and transmission control module # 41 "B"
- 7 and transmission control module # 26 "C"
- 8 and transmission control module # 13 "PA"

- Check for a short-circuit to supply voltage.
- Proceed to: Checking Gear-shift Position Sensor section below.





Checking Gear-shift Position Sensor Operation
- Ignition OFF.
- Connect transmission connector C.
- Transmission control module connected.
- Ignition ON.
- Go into scrolling values.
- Read gear-shift position sensor position.
- Move the gear-shift position sensor to all shift positions a number of times, and repeatedly select the same position to check the operation of the gear-shift position sensor.
- Are all values OK?

If reading is OK:
- Proceed to: Remedy Contact Resistance And Oxidation section below.

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





Remedy Contact Resistance And Oxidation
- Ignition OFF.
- The diagnostic trouble code (DTC) was caused by loose connections in the transmission control module and transmission connectors.
- Check connectors for contact resistance and oxidation and remedy.
- Proceed to: Verification section below.





Replacing Component
- Try a new gear-shift position sensor.
- Proceed to: Verification section below.





Checking Gear-shift Position Sensor
- The gear-shift position sensor can malfunction if the signal cable has been short-circuited to supply voltage. Check the gear-shift position sensor as follows:

- Ignition OFF.
- Transmission connector C connected.
- Transmission control module connected.
- Ignition ON.
- Go into scrolling values.
- Read gear-shift position sensor position.
- Move the gear selector to all shift positions a number of times, and repeatedly select the same position to check the operation of the gear-shift position sensor.

- Are all values OK?

Yes:
- Fault corrected.

No:
- Proceed to: Replacing Component section above.





Verification
After repairs have been completed they must be verified as follows to ensure that the fault has been eliminated:

- Ignition OFF.
- Reinstall components, reconnect connectors etc.
- Ignition ON.
- Go into scrolling values.
- Read gear-shift position sensor position.
- Move the gear selector to all shift positions a number of times, and repeatedly select the same position to check the operation of the gear selector.

- Are all values OK?

Yes:
- Fault corrected.

No:
- Proceed to: Fault-tracing Information section below.

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: Checking Gear-shift Position Sensor section above.





Intermittent Fault
- Check that the gear-shift position sensor is securely attached.
- Check transmission control module and transmission connectors and gear-shift position sensor ground terminal for loose connections and contact resistance and oxidation.
- Check cables between the gear-shift position sensor and transmission control module for an intermittent open-circuit, intermittent short-circuit to ground and an intermittent short-circuit to supply voltage.
- Proceed to: Fault-tracing Information section below.

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: Checking Gear-shift Position Sensor section above.

No:
- Operation done.
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