Movement When Not Permitted

LA. Diagnostic trouble code (DTC) information





Condition
Motor 4 controls the height of the seat at the front edge.
If the control module receives a signal from the potentiometer that motor 4 is operating, even though the control button for seat front height adjustment is not being activated, then diagnostic trouble code (DTC) PSL/PSR-133 is set.

Possible source
- Wiring to motor 4 incorrectly connected.
- Wiring to potentiometer 4 incorrectly connected.
- Wiring pinched or damaged.
- Defective control module.

Fault symptom(s)
- The seat moves at the front edge when forward/backward adjustments are being made or when the rear edge is being adjusted.
- The front edge of the seat moves only a short moment before automatic shutdown occurs.
- Fault-tracing begins at LB. Movement when not permitted.





LB. Movement when not permitted

LB1: Checking potentiometer signal
- Ignition OFF.
Select scrolling values and read off the value from potentiometer 4.

Use the control buttons to adjust the seat forward/backward, the backrest angle and the height adjustment at front and rear seat edges.

The value from potentiometer 4 should only be affected when the seat front edge is adjusted and not when the other functions are affected. Front edge adjustment should stop when the button is released.

If reading is OK:
- LB7

If reading is incorrect:
- LB2





LB2: Checking connections on leads
- Ignition OFF.
- Remove seat from car.
Check and correct incorrectly connected leads to motor 4 and to the potentiometer on motor 4.

Switching connections:
- Press the pins out of connector C for the leads that are to be switched over. Use terminal removal tool 951 2631.
- Switch the leads and press the pins into the connector.

Were there any problems with connections?

Yes:
- LB5

No:
- LB3





LB3: Checking wiring for short-circuits
- Ignition OFF.
- Disconnect the black 14-pin connector C and the 3-pin connector on potentiometer.
- Check the yellow/red signal lead in the black 14-pin connector, terminal C:11 and the two other yellow/red signal leads, C:9 and C:10, for short-circuit between the two leads.

Was a fault detected?

Yes:
- LB5

No:
- LB4





LB4: Replace component
The motors and potentiometers are correctly connected and the leads are not damaged.
Try a new control module. Control module, Service and Repair

Then continue with:
- LB5





LB5: Verification
Hint: Afier carrying out the repair, check that the fault has been remedied as follows:
- Ignition OFF.
- Reinstall components, connectors etc.
- Connect up seat in car.
Select scrolling values and read off the value from potentiometer 4.

Use the control buttons to adjust the seat forward/backward, the backrest angle and the height adjustment at front and rear seat edges.

The value from potentiometer 4 should only be affected when the seat front edge is adjusted and not when the other functions are affected.

It reading is OK:
- Fault corrected

If reading is incorrect:
- LB6

LB6: Fault-tracing information
The verification result shows that the fault persists.
Do you want to exit fault-tracing?

Yes:
- Fault not corrected

No:
- LB1





LB7: Intermittent fault
Check the yellow/red signal lead in the black 14-pin connector, terminal C:1 1 and the two other yellow/red signal leads, C:9 and C:10, for intermillent short-circuit between the two leads.

The fault can also be due to a relay in the control module temporarily sticking in the closed position but then releasing and opening correctly.

If the fault persists after verification, try a new control module.

Then continue with:
- LB8

LB8: 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:
- LB1

No:
- Operation done.