Emergency Operation Of Electrically Adjustable Seat
If electrical adjustment is out of order, the seat cannot be moved longitudinally to gain access to the retaining bolts. It will then be necessary to fabricate a tool so that the seat can be moved manually.
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- Raise the seat to its highest position. Electrically adjustable seat: There is a protective cap on the tip of the front screw. Keep this cap safe and refit it to the screw to prevent damage to the electrical cables.
- Remove the upper seat cowl.
- Unscrew the front bolt from the lower cowl.
- Remove the bevel gear which moves the seat longitudinally, 2 torx 30 screws. Grasp the shaft coming from the other side of the seat chassis and pull the bevel gear outwards.
- Dismantle the bevel gear, 2 or 3 torx 20 screws.
- Press in the clip securing the plastic bush and withdraw the shaft. Wipe the grease off the shaft when it has been removed.
- Fit special tool «75 19 531 PROTECTIVE COLLAR (TYPE 10)»(ref-278633-S42549787062008013000000) on the gear and secure it with a suitable hose clip.
- Press as large a screwdriver as possible into the other end of the hose so that its blade reaches the end of the shaft. Secure with a hose clip as far from the screwdriver handle as possible.
- Fit the "tool" on the shaft and turn the screwdriver to move the seat until the retaining bolts are accessible. NOTE: Aid moving the seat by pressing it backwards or forwards as appropriate.
- Remove the seat, see «To remove»(ref-278633-S35830952912008013000000).
Description of operation
The ACC unit supplies the heating element with a B+ voltage from K2 pin 1 which is then grounded via G 14. The heating element in the passenger seat is supplied with a B+ voltage from K2 pin 6 and is grounded via G 24.
The temperature sensor (254) is grounded internally in the ACC unit via K1 pin 23 for both driver's seat and passenger seat
The driver's seat sensor is supplied from K2 pin 4 with 5V via a 6.8 Kohms resistor built into the ACC unit. The characteristics of the NTC resistor mean that resistance decreases afterwards as the temperature increases. This means that the voltage measured over the resistor will at the same time decrease during rising temperatures.
The passenger seat sensor is supplied from K2 pin 5 with 5V via a 6.8 Kohms resistor built into the ACC unit. The characteristics of the NTC resistor mean that resistance decreases afterwards as the temperature increases. This means that the voltage measured over the resistor will at the same time decrease during rising temperatures.
The voltage value from the sensor is A/D converted and is then available in digital form. The digital voltage value is then converted to temperature and is added to the ACC unit's operating memory. Voltage values close to 0 or 5V are interpreted as faults in the circuit.
The fans in the ventilated seats are controlled manually with pushbuttons in the ACC panel. The LEDs in the buttons show fan speed. The preconditions are that the engine is running and that the cabin fan knob is not in the OFF position.
The fan speed in the driver's seat and passenger seat is controlled by a voltage
Step 1: low speed approx. 9.3 volts
Step 2 : high speed approx. 11 volts
The ACC unit's K1 pin 2 is connected to the driver's seat fan and is grounded via G14 and K1 pin 11 to the passenger seat's fan that is grounded via G24.
| Step | Indication in button | Current consumption (A) |
|---|---|---|
| 0 | None | 0 |
| 1 | 1 LED | Approx. 1.3 |
| 2 | 2 LEDs | Approx. 2 |
CURRENT CONSUMPTION REFERENCE
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Rear seat heating is available as an option for the Saab 9-5. The rear seat is then fitted with two heating pads, one in each seat.
The heating is controlled manually and can only be turned on when the ignition is ON. The heating time is controlled by TWICE and depends on the exterior temperature.
Scheme 7
When the switch (252R) for the heated rear seat is pressed, B+ is supplied to pin 9 in TWICE. TWICE grounds the relay for the heated rear seat via pin 52.
The relay trips and supplies B+ via fuse 10 to the heating pad in the rear seat and to the switch indicator.
The length of time the heating is active depends on the exterior temperature. TWICE receives information on the exterior temperature from SID via the bus.
When the outside temperature exceeds -5 °C, the heating will be on for 5 minutes. If the outside temperature is lower than -5°C, it will stay on longer. At -14°C it will have reached its maximum activation time. This is programmable from 3-18 minutes but is normally preset to 10 minutes.
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To avoid loading the battery more than necessary when the starter motor is activated (+15 ON, +54 OFF), TWICE switches off the electric heating. When the ignition key is then turned back from ST to ON, TWICE turns the heating on again.
For safety reasons, the length of time it is disconnected is maximized at 20 seconds so that the heating works even if +54 is missing in the event of a fault.
TWICE receives information on the ignition +54 from DICE via the bus. Ignition +15 is connected to pin 16 of TWICE.
The electric operation is powered with +30 circuit from fuse 11. The power supply is relay-controlled and the relay grounded via pin 3 in TWICE.
TWICE supplies power to the passenger seat by grounding the relay when the ignition is ON or one of the front doors is open. The seat cannot be adjusted while the starter motor is running.
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 forwards or backwards
- 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 inclination.
Brief Description, PSM System
The PSM system (Power Seat Memory) is available as an integral part of the electrically adjustable front seat. This provides a memory function for the driver's seat in which 3 different seat settings can be stored and recalled by pressing a memory button.
An electrically adjusted driver's seat with PSM has a control module and a switch with four buttons; 3 memory buttons for programming and one store button to activate the memory.
See also:
• CRIMP CONNECTION J93, REAR HARNESS