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Potentiometer Signal Too High






Potentiometer signal too high

Checking status




- Ignition off.
Read off value from the potentiometer for motor 2.
Adjust the seat backrest forward and backward between the seat end positions several times using the control button.





The potentiometer value must not exceed 4.6 V at any time.

OK - Intermittent fault

Not OK - Checking resistance in circuit to potentiometer

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Checking resistance in circuit to potentiometer








- Ignition off.
- Remove seat from car according to Replacing seat assembly Replacing Seat Assembly.
- Disconnect the gray 14-pin connector B.
Connect an ohmmeter between terminal B:4 and B:5 on the gray 14-pin connector (potentiometer side).













The ohmmeter should read approximately 2200 ohms.

OK - Checking the supply and signal leads on the potentiometer

Not OK - Checking potentiometer resistance

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Checking potentiometer resistance








- Ignition off.
- Disconnect the gray 14-pin connector.
- Remove potentiometer on motor 2.
Connect an ohmmeter between the two outer terminals on the potentiometer.









The ohmmeter should read approximately 2200 ohms.

OK - Checking potentiometer ground lead

Not OK - Replacing component

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Replacing component
Test with a new potentiometer according to Motor and potentiometer in backrest, replace Motor and Potentiometer In Backrest, Replace.

Continue - Verification

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Checking potentiometer ground lead








- Ignition off.
- Disconnect the 3-pin (TCM) connector to potentiometer on motor 2.
- Disconnect the gray 14-pin connector B.
Connect an ohmmeter between the gray 14-pin connector terminal B:4 and the corresponding terminal on the 3-pin connector (yellow/white cable).









The ohmmeter should read approximately 0 ohms.

OK - Checking contact resistance and oxidation

Not OK - Checking for an open-circuit

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Checking for an open-circuit
Check the yellow/white ground lead between the control module, terminal B:4 and the potentiometer for an open-circuit according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Continue - Verification

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Checking contact resistance and oxidation
Check the 3-pin connector to the potentiometer on motor 2 for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Continue - Verification

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Checking the supply and signal leads on the potentiometer








- Ignition off.
- Disconnect the gray 14-pin connector B.
Connect an ohmmeter between the power supply cable, terminal B:5, and the two power supply cables to the motor, terminals B:1 and B:2, in the gray 14-pin connector (potentiometer side).
Connect an ohmmeter between the signal cable, terminal B:3, and the two power supply cables to the motor, terminals B:1 and B:2, in the gray 14-pin connector (potentiometer side).









Ohmmeter should read infinite resistance for all readings.

OK - Checking control module and connector B

Not OK - Checking for a short-circuit

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Checking for a short-circuit
The measurements show that the signal cable or supply lead to the potentiometer is short-circuited to battery voltage.
Check the blue/white power supply cable between terminal B:5 and the potentiometer on motor 2 for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
Check the white signal cable between terminal B:3 and the potentiometer on motor 2 for a short-circuit to supply voltage according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.









Continue - Verification

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Checking control module and connector B
Potentiometer and cables are OK.
Check the 14-pin gray connector B for contact resistance and oxidation according to Checking wiring and terminals. Permanent fault Checking Wiring and Terminals. Permanent Fault.
If the fault persists after verification, try a new control module according to Control module, replace Control Module.





Continue - Verification

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Verification




Verification

Hint: 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.
- Connect seat to car..
Read off the value from the potentiometer on motor 2.
Adjust the seat backrest forwards and backwards between the seat end positions.





The value from potentiometer 2 must not exceed 4.6 V or fall lower than 0.2 V at any time.

OK - VERIFIED

Not OK - VERIFICATION FAILED

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VERIFIED - FAULT FOUND

VERIFICATION FAILED - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
The fault should have been detected and remedied. As this is not the case fault-tracing has failed.
Exit fault-tracing for this diagnostic trouble code (DTC) or make another attempt.

Do you want to exit fault-tracing?

Yes - Exit fault-tracing

No - Attempt New Test

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Attempt New Test - Checking status

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Intermittent fault





Potentiometer signal too high. Intermittent fault

Checking cables and connectors
Check the gray 14-pin connector B and the connector on the potentiometer on motor 2 for loose connections according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults and contact resistance and oxidation according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check the ground lead between the control module, terminal B:4 (yellow/white cable), and the potentiometer on motor 2 for an intermittent open-circuit according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.
Check the signal and power supply cables between the control module and the potentiometer on motor 2, terminal B:3 and B:5 for an intermittent short-circuit to supply voltage according to Checking wiring and terminals. Intermittent faults Checking Wiring and Terminals. Intermittent Faults.













Continue - Fault-tracing information

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Fault-tracing information




Information

Fault-tracing information
If the fault is intermittent, do not verify fault-tracing if the fault does not recur.
It is possible to view the information again, or leave fault-tracing for this diagnostic trouble code (DTC).

Do you want to view the information again?

Yes - Attempt New Test

No - FAULT FOUND

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Attempt New Test - Checking status

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