P0462 on GMC
Fuel Level Sensor 'A' Circuit Low Input
P0462 on GMC vehicles indicates fuel level sensor 'a' circuit low input. Au7o has documented this code across 2 GMC models — most commonly on Sierra 1500, Sierra 3500HD. P0462 indicates the powertrain control module detected a fuel-level sensor signal voltage that is lower than the normal operating range — often interpreted as an empty or near-empty reading that may not reflect the actual fuel amount. The fuel level sender reports tank level via a variable resistance, and an abnormally low signal can stem from a short to ground or a failed sender. This usually shows up as a stuck-low or inaccurate fuel gauge rather than a driving problem. It is low-urgency but should be corrected so the gauge and EVAP monitors work properly. Typical repair costs on GMC range from $250 to $1,100, depending on the specific model and root cause.
Common Causes of P0462
- •Faulty fuel level sensor / sending unit
- •Short to ground in the signal wire
- •Corroded or damaged connector at the fuel pump module
- •Open or high-resistance ground circuit
- •Worn sender resistor card or float
- •Damaged wiring harness to the tank
- •Instrument cluster or PCM fault (less common)
P0462 on GMC by Model
GMC Sierra 1500(1 issue)
- Fuel Level Sensor Failure Causing Erratic or Inoperative Gas Gauge2003-2007
A very common GMT800 complaint is sulfur contamination and wear of the fuel level sensor contacts inside the tank module, causing the gauge to read empty, full, or fluctuate unpredictably. Owners often see a low-fuel warning with plenty of fuel in the tank or watch the gauge drop suddenly while driving. GM issued service information and special coverage on many trucks for this exact condition.
GMC Sierra 3500HD(1 issue)
- Fuel Tank Strap and Fuel Sender Unit Corrosion Causing Fuel Gauge Inaccuracy2007-2014
On 2007–2014 Sierra 3500HD models, the fuel tank mounting straps and the fuel level sender unit are prone to corrosion, causing inaccurate fuel gauge readings and in some cases complete sender failure. NHTSA complaint data documents numerous owners reporting sudden fuel gauge drops to empty or erratic readings unrelated to actual fuel level. The plastic float arm on the sender can also crack, exacerbating the problem.
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View P0462 across all makes →Frequently Asked Questions
What does P0462 mean on GMC?▼
P0462 stands for "Fuel Level Sensor 'A' Circuit Low Input." P0462 indicates the powertrain control module detected a fuel-level sensor signal voltage that is lower than the normal operating range — often interpreted as an empty or near-empty reading that may not reflect the actual fuel amount. The fuel level sender reports tank level via a variable resistance, and an abnormally low signal can stem from a short to ground or a failed sender. This usually shows up as a stuck-low or inaccurate fuel gauge rather than a driving problem. It is low-urgency but should be corrected so the gauge and EVAP monitors work properly. On GMC specifically, this code is documented across 2 models.
What causes P0462 on GMC vehicles?▼
Common causes on GMC: Faulty fuel level sensor / sending unit, Short to ground in the signal wire, Corroded or damaged connector at the fuel pump module, Open or high-resistance ground circuit, Worn sender resistor card or float. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0462 on a GMC?▼
Repair costs on GMC range from $250 to $1,100, depending on the specific model and root cause.
Which GMC models have P0462 documented?▼
Au7o has documented P0462 on 2 GMC models: Sierra 1500, Sierra 3500HD.