Setevarmen vil ikke på (e39).

[haakon85]

Var litt småkaldt når jeg satt meg i bilen i dag morges så jeg skulle sette på setevarmen.

Trykte på knappen og fikk grønt lys, men etter ca. 2 sek. sluknet det igjen. Prøvde å stille justeringen på ulike nivå men fremdeles vil den ikke.

Har bare eid bilen noen dager og dette er min første BMW. Det første som slo meg var at det kunne være et relé som krangler. Noen her som har et konkret svar?

[Ole-J]

Slenger meg på denne da jeg har samme problem på MIN nyinnkjøpte e39.

[Brag3]

kontrollert sikringer?

[bcrazy]

Sannsynlig at varme elementet i setet er defekt.

Går an å bytte. Finnes diy på nettet.

[haakon85]

Liten oppdatering: Prøvde på nytt her isted. Den ser ut til å kunne holde seg på så lenge du styrer unna full styrke, da kutter den. Varmeelementet som holder på å ta kvelden da eller?

Har ikke begynt noen omfattende feilsøking enda. Er midt i flytting så har ikke så mye tid til å dulle med bilen akkurat nå.

[jolly]

Elementet på setevarme i E39 er en matte som sitter i både pute og rygg. Den består av tynne tråder som desverre lett ryker.

Klassikeren er at en skal plukke ut noe i baksetet , og setter kneet i sitteputa på fremsetet.

Det er faktisk nok til at du får et brudd i elementet. Det går an å skifte , men er litt "kødd" .

Om du ikke har skinn....finn et brukt i samme farge der elementene funker...du får de for 500-1000. Gs har brukt skinn nå til 5000.-

Element koster like mye..og du har spart deg mye arbeid.

[haakon85]

Bumper denne her litt jeg.

Er det noen som vet hvor jeg finner reléene til setevarme? Har snakket med et par folk, og flere mener det er et relé som lager kødd.

[Nietsoj]

Hei, jeg har samme problemet.... jeg har ikke hatt tid til og fårske på det pga er i millitæret..

Når jeg kommer hjem skal jeg prøve og søke litt om det er kortslutning i setet eller ikke får da håpe det er helt... kjøpt bilen brukt med skinnseter så det blir kaldt uten varmer på vinteren ja

[///Naitsirk]

Er ikke noe relee på den kretsen...

Seat heating

The seat heating system heats the seat cushion area and backrest. The electronics for controlling the selected heating temperature (3 stages) and fault monitoring are integrated in the switch centre of the centre console.

Function

Seat heating can be switched on in three heating stages as from terminal 15 by pressing the button. Three LEDs built into the switch centre light to indicate operation. "Terminal 15 active" is signalled to the centre console switch centre via the K-bus.

Initially, heating stage 1 is activated when the seat heating is switched on (button pressed once). The seat surface is heated up to approx. 44 °C. All three LEDs light to indicate operation.

By pressing the button once more, the topmost LED goes out and heating stage 2 is activated. The seat is now only heated up to 39 °C.

The seat heating system is switched to heating stage 3 by pressing the button once again. The bottom-most LED lights. The seat is heated up to 35 °C.

The seat heating is switched off by pressing the button once again or switching off the ignition. The seat heating can also be switched off in any heating stage by pressing the push button for longer than 1 second.

The seats are heated by means of carbon fibre heating mats in the main section and steel wires (steel filaments) in the bolster. A carbon fibre heating mat is installed in both the seat cushion section as well as in the backrest. The centre sections of the seat and backrest as well as the bolsters of the seat and backrest are always heated. Heating filaments or carbon fibre mats are additionally integrated in the thigh support on sports seats. The seat and backrest bolsters are not heated on the series E39 sports seat with fabric cover.

The temperature is measured by a temperature sensor in the seat upholstery and passed on to switch centre.

Monitoring functions

Battery voltage

The electronic seat heating control switches off the power supply to the heating mats if the battery voltage in the vehicle is less than 11.4 V ±0.3 V. The function LEDs however remain on. Power supply to the heating mats is restored when the battery voltage is greater than 12.2 V ±0.3 V for at least 5 seconds.

PC-Board temperature

Due to the fact that the power input of the seat heating system is very high (120 W), the temperature of the pc-board in the switch centre is monitored by temperature sensors. Initially, the heating power is reduced as the temperature increases to over 85 °C. The heating is switched off if the pc-board temperature exceeds 95 °C. The function LEDs however remain on. The seat heating cuts in automatically again when the pc-board temperature drops below 85 °C.

Fault monitoring

The electronic seat heating control system monitors the temperature sensor and heating mats for faults. Detected faults are stored in the fault code memory of the centre console switch centre.

The following faults can be recognized:

•Short-circuit or line break

•Short-circuit or line break of temperature sensors

•Break in heating mats

If a break or short occurs at the temperature sensor, the seat heating is switched off in order to prevent overheating. The function LEDs are switched off.

Current measurement, seat heating

The current is measured in order to be able to provide a basic statement with regard to a defect in the seat heating system.

Measurement preparation

On vehicles equipped with a switching centre in the centre console, the current is measured directly at the switching centre.

•Switch off seat heating

•Remove centre console switching centre (A169)

•Measurement is carried out with a 50 A clip-on ammeter

•Unwind insulating tape from wiring harness under seat and attach clip-on ammeter to the wire to be measures.

•Left seat heating: Measurement on HZFA wire (white/yellow, pin 1)

Right seat heating: Measurement on HZBF wire (white/green, pin 13)

•Start engine in order to ensure a system voltage of approx. 13.8 V

System voltage

If the system voltage drops below 11.4 V, the LEDs remain lit but the seat heating is switched off. The seat heating is re-activated as soon as a voltage of at least 12.2 V is permanently applied.

Measurement at DIS tester

•Select "measurement system"

•Measurement function: Current 50 A

•Measurement connection: Clip-on ammeter

•Type of measurement: Direct current =

•Measuring range: +/- 50 A

•Check system voltage with DIS tester

•Switch on seat heater on the side to be measured

Measurement evaluation

Generally applicable for all heating stages: Each heating stage has a certain setpoint temperature. The control unit attempts to reach this temperature as fast as possible. The temperature is the kept constant by means of clocking (= pulsating direct current).

•Generally, the current is approx. 10 A during the heating-up phase (at a system voltage of 13.8 V)

•The heating output is reduced on approaching the setpoint temperature. The clocking function can now be distinctly recognized, i.e. the current pulsates between 0 and approx. 10 A.

•On finally reaching the setpoint temperature, the interval of the 0 A range is extended even longer.

•If the current temperature is higher than the setpoint temperature, e.g. when, after a longer period of operation, the heating is switched back from stage 1 (3 LEDs) to stage 3 (1 LED), no current is applied until the temperature has again dropped to the corresponding setpoint temperature.

Heating-up seat

The duration of the heating-up phase is dependent on the temperature measured at the temperature sensor! The setpoint temperature is reached more quickly at high ambient temperatures (e.g. in summer) or if the seat is preheated. In this case, the clocking cuts in correspondingly earlier.

Measured power

The measured power depends on many different factors. Both the level of the system voltage as well as the type of seat installed and operation of other loads (seat heating on other side, steering wheel heating) play a significant role. The specified value of 10 A is therefore only a reference value.

Setpoint temperatures

The following setpoint temperatures are reached in the three-stage seat heating system:

•Stage 1 operation (3 LEDs lit):

The seat is heated to a setpoint temperature of 35 °C

•Stage 2 operation (2 LEDs lit):

The seat is heated to a setpoint temperature of 39 °C

•Stage 3 operation (1 LED lit):

The seat is heated to a setpoint temperature of 44 °C

Measurement evaluation

•A current of approx. 10 A is applied:

The seat heating is OK

•A current of approx. 5 A is applied:

Defect in heating mat of seat cushion or seat backrest

•No current is applied:

Defect in heating mat of seat cushion and seat backrest