Engine-Codes - Mercury - B1203 MERCURY

B1203 MERCURY - Fuel Sender Circuit Short To Battery

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

B1203 MERCURY Possible Causes

  • Faulty Fuel Level Sensor Unit
  • Fuel Level Sensor Unit harness is open or shorted
  • Fuel Level Sensor Unit circuit poor electrical connection

How do I fix code B1203 MERCURY?

Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

Cost of diagnosing the B1203 MERCURY code

Labor: 1.0

The cost of diagnosing the B1203 MERCURY code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

B1203 MERCURY Meaning

The fuel pump module is hardwired to the Instrument Cluster (IC). The fuel level sensor (part of the pump module) is a variable resistor actuated by a float with resistance ranging between 180 ohms ± 4 ohms at empty (E) to 10 ohms ± 2 ohms at full (F). The instrument cluster (IC) provides a reference voltage to the fuel pump module on the input circuit. As the fuel level changes, the fuel level sensor float moves up or down according to the fuel level altering the fuel level signal voltage through the resistor. The instrument cluster (IC) interprets this signal and commands the fuel gauge pointer to sweep to the correct level.

B1203 MERCURY More Information

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