What Does B1228 Mean?
This diagnostic trouble code indicates that the body control module (BCM) or powertrain control module (PCM) has detected an abnormal voltage condition in the fuel temperature sensor #2 circuit. Specifically, the control module has identified that the circuit voltage is higher than expected, consistent with a short to battery voltage (typically 12-14 volts). This sensor monitors fuel temperature to allow the module to compensate for fuel density changes and optimize engine performance.
Common Causes
45%
Damaged wiring harness or chafed insulation causing wire-to-power short between sensor and module
30%
Failed fuel temperature sensor #2 with internal short circuit to voltage supply
15%
Corroded or damaged connector pins at sensor or module causing cross-circuit contamination
10%
Control module internal fault with sensor circuit driver or voltage reference
Diagnostic Steps
1
Step 1: Perform visual inspection of fuel temperature sensor #2 location (typically in fuel tank, fuel rail, or fuel line) and examine all associated wiring for visible damage, chafing against sharp edges, heat damage, or pinch points where wire insulation may be compromised
2
Step 2: Disconnect fuel temperature sensor #2 connector and use a digital multimeter to measure voltage on the signal wire at the harness side (module side) with ignition on; reading should be approximately 5 volts (reference voltage) - if battery voltage (12-14V) is present, wiring harness has short to power
3
Step 3: With sensor disconnected and ignition off, measure resistance between sensor signal pin and battery positive; reading should be infinite (open circuit) - any measurable resistance or continuity indicates short to battery in harness wiring
4
Step 4: If wiring tests normal, connect multimeter to fuel temperature sensor terminals and measure resistance; compare to manufacturer specifications (typically 2000-3000 ohms at room temperature for NTC thermistors) - out-of-range or erratic readings indicate failed sensor
5
Step 5: Inspect connector terminals at both sensor and module ends for corrosion, bent pins, moisture intrusion, or terminal spread that could cause cross-contamination between adjacent circuits
6
Step 6: After repairs, clear codes, perform fuel system operational test, and monitor live data for fuel temperature sensor #2 signal voltage (should read 0.5-4.5V depending on fuel temperature) to verify proper circuit operation
Estimated Repair Cost
$150 - $600
Parts + labor, varies by vehicle and location
This diagnostic trouble code indicates that the body control module (BCM) or powertrain control module (PCM) has detected an abnormal voltage condition in the fuel temperature sensor #2 circuit. Specifically, the control module has identified that the circuit voltage is higher than expected, consist...
The most common cause of B1228 (Fuel Temperature Sensor #2 Circuit Short to Battery) is: Damaged wiring harness or chafed insulation causing wire-to-power short between sensor and module
Typical repair costs for B1228 range from $150 to $600, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is generally safe to drive in the short term, but fuel mixture calculations may be less accurate affecting performance and fuel economy. Repair within 1-2 weeks to prevent potential fuel system performance issues and avoid engine running rich or lean conditions.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1228 to identify the root cause.
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Quick Info
Category
Body
System
Fuel System
Difficulty
Type
Manufacturer
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