Powertrain, generic (extended)

P25D9 Fuel Level Sensor C Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P25D9 reports that the signal of the third fuel level sender has dropped below its lowest valid value. With the usual resistor-type sender this points to very low resistance, typically a signal wire shorted to ground or a sender shorted internally. Whether low means empty or full depends on how the sender is wired, so the gauge may stick at either end. No manufacturer documents P25D9 publicly. For sender A, Ford uses a fixed limit as reference: below 5 ohms, which equals less than one A/D count, the low code is set after 30 s (P0462). CARB requires out-of-range checks on all fuel level inputs. Distinct from P25DA, the high fault, and from P25D7, which only states a general circuit problem. Expect a gauge pinned at one end and a stored lamp code.

Likely causes

Signal wire of sender C chafed and shorted to ground
Internal short in sender C
Water in the tank connector bridging signal and ground

Symptoms

  • Gauge pinned at full or empty
  • Check engine lamp on

Repair estimate

DifficultyMediumDIY possible
Parts and labour€50–600
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

fuel level sensor cwiring harness

Related codes

P25D7P25DAP25DBP0462P2067

References: law.cornell.edu, fordservicecontent.com.