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Fault diagnosis, fuel gauge (MIU 1)

Fault diagnosis, fuel gauge (MIU 1)

Fault symptoms

The fuel gauge shows empty.

Low fuel indicator lamp on.

Diagnostic procedure



1. Unplug the fuel level sensor connector (located under a cover in the rear seat) and take a resistance reading across the pins.

The correct resistance is between 50 and 390 ohms: 305 ohms (3/4), 220 ohms (1/2), 135 ohms (1/4) and 100 ohms (10 L). If the reading obtained is outside this resistance range the sensor or its wiring is faulty. Investigate the cause.

2. If the resistance is OK, continue by checking the wiring between the fuel level sensor and the main instrument display panel. Remove the main instrument display panel and its three connectors.



3. Plug in the fuel level sensor connector. Check for continuity/shorting between pin 6 (14-pin connector) and pin 8 (black 12-pin connector) of the main instrument display panel connectors. The correct resistance reading is as given in point 1.

If the reading obtained is outside this resistance range the wiring is faulty. Investigate the cause and rectify.

4. Check the conductive foil on the rear of the main instrument display panel for an open circuit between pin 6 (14p) and the screw marked "F SIG" and between pin 1 (12p-2) and the screw marked "GND" behind the fuel gauge on the main instrument display panel.


If the conductive foil is intact and the fuel gauge does not work, the fault is probably in the gauge. The complete main instrument display panel will have to be changed. If there is an open circuit in the conductive foil, change the foil.