- disconnect the wire from the negative terminal of the battery;
- remove the instrument panel panel as described in Section 8 "Body";
- unscrew the screws securing the instrument cluster to the instrument panel trim and, pulling it towards you, remove the instrument cluster from its socket;
- disconnect the wiring harness from the instrument cluster.
Install the instrument cluster in the reverse order of removal.
Diagnostics of the instrument cluster on the car.
1. Turn on the ignition. Press the trip meter reset button and, after turning on the ignition, release it. After this, the instrument cluster enters the "test" mode:
- the arrows of all instruments move three times over the entire range of the scale;
- all segments of the liquid crystal display (LCD) are illuminated.
2. After this, it is necessary to clear the memory of the electronic instrument cluster processor by pressing the odometer reset button for at least 5 seconds.
3. Retest. Then briefly press and release the odometer reset button. The LCD will display the processor software version number (Uer 0.8, Uer 1.1 or other).
4. When you press the reset button again, one of the following codes will appear:
- 0 - no faults;
- 1 - the microprocessor is faulty;
- 2 - open circuit of the fuel level indicator sensor;
- 4 - increased voltage of the on-board network (more than 16+1.8 V);
- 8 - low voltage of the on-board network (less than 8-0.6 V).
If there are several faults, the corresponding sum of codes is displayed, for example: 6 (2+4), 10 (2+8), 12 (4+8), 14 (2+4+8).
Checking the instrument cluster. The instrument cluster is checked in accordance with the technical conditions for delivery on the stand using special equipment (pulse generator, stabilized power supply, resistor box, etc.). Reference data for testing devices (at a supply voltage of 13.5±5 V and a temperature of 23±3°C) are given in Tables 7-9, 7-10, 7-11 and 7-12.
Table 7-9. Speedometer Test Data
Table 7-10. Tachometer Check Data
Table 7-11. Fuel gauge test data
Table 7-12. Coolant Temperature Gauge Test Data
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