Checking the Hopple Level Sensor

The fuel level sensor is located at the top of the fuel tank. As the fuel level drops, the sensor float drops. This increases the electrical resistance associated with the float variable resistor. As a result, the voltage supplied to the indicator on the front panel decreases and the indicator shows a decrease in the fuel level in the tank.

With a further decrease in the fuel level for some car models, in a certain position of the float, the signaling contact closes and the signal lamp of the reserve fuel supply lights up on the front panel. The fuel level sensor must be checked if the fuel level gauge shows either too low or too high fuel level, or shows nothing at all.

Test conditions: All electrical connections must be checked for damage.

Remove the fuel level sensor.



Model from 5/87: Install the level sensor in the position indicated in fig. position and measure the resistance of the sensor in this position. Connect an ohmmeter to terminals 3 and 4 of the connector.

Models from 4/87 and all-wheel drive models: Place the fuel level sensor in a horizontal position and measure the electrical resistance of the sensor. On all-wheel drive vehicles, connect an ohmmeter to the float housing and the connecting plug. Position "E" corresponds to an empty tank, position "F" full tank.

Resistance value

If the measured resistance value does not match the specified value, the sensor must be replaced

Install the sensor.