C70, S70 & V70 (Fuel Gauge Reading Incorrect)

Turn ignition off. Remove right side panel in trunk. Disconnect Black 2-pin fuel level sensor connector. See Figure. Connect an ohmmeter between connector terminal No. 2 (Yellow/Red wire) and ground. If zero ohms is present, go to next step and check fuel level sensor. If zero ohms is not present, check Yellow/Red wire between connector in trunk and 30-pin instrument cluster connector.
Turn ignition off. Locate fuel level sensor Black 2-pin connector behind right side panel in trunk. Connect ohmmeter between connector terminals on fuel level sensor side of harness.
Depending on amount of fuel in tank, if ohmmeter indicates 7.5-12.5 to 322.5-327.5 ohms, replace instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION. If ohmmeter does not indicate 7.5-12.5 to 322.5-327.5 ohms, replace fuel level sensor. See FUEL LEVEL SENSOR under REMOVAL & INSTALLATION. If amount of fuel in tank is unknown, remove fuel level sensor from tank and turn it upside down.
Connect an ohmmeter between fuel level sensor connector terminals. Turn sensor slowly to same position as that in tank. Resistance should rise from about 10 ohms (full tank) to about 325 ohms (empty tank). If resistances are incorrect, replace fuel level sensor. See FUEL LEVEL SENSOR under REMOVAL & INSTALLATION. If resistances are correct, replace instrument cluster. See INSTRUMENT CLUSTER under REMOVAL & INSTALLATION.