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Electrically adjustable passenger seat

Electrically adjustable passenger seat



The passenger seat is operated with the switch in the side panel on the seat. Electric motors move the seat lengthways, change the height of the front and back of the seat and change the reclining position of the backrest.

Description of operation

The electric operation is powered by the +30 circuit from fuse 11. The power supply is relay-controlled and the relay is grounded via pin 3 in TWICE.

TWICE powers the passenger seat by grounding the relay when the ignition is in position ON or one of the front doors is opened. The seat can be adjusted for 30 seconds after the door has been closed but not while the starter motor is cranking.

When the ignition is ON (+15 and +54 circuits), power is provided permanently to the switch in the passenger seat. When the ignition is OFF and a front door is open, power is supplied for 20 minutes. If the door is shut and then opened again, power is supplied for a further 20 minutes.

The switch controls the following motors:


electric motor (357Pa) moves the seat forward or back

Electric motor (357Pb) raises or lowers the front of the seat

Electric motor (357Pc) raises or lowers the rear of the seat

Electric motor (357Pd) changes the backrest angle.


Bus communication

DICE supplies information to TWICE on the +54 ignition (On/Off) so that TWICE can check whether the starter motor is cranking.

For further information on the TWICE system, see group 3, Central Electronics, ”TWICE”.

Diagnostics

In the event of a fault in the relay control circuit, diagnostic trouble code B1535 will be generated in TWICE. The diagnostic trouble code is generated if there is a:


Open circuit or short circuit to ground

Short-circuit to B+


The diagnostic trouble code is not generated when the voltage is below 11V or during diagnostic communication. The control module output can be activated with the diagnostic tool.