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P0500 VSS Error Code: What Happens if You Apply 12V Constant Power to the Vehicle Speed Sensor?

Model: VSS error code P0500 Fault Code: P0500 Posted: 2007-03-03 15:57

I accidentally applied a constant 12V power supply to my vehicle speed sensor (VSS). I'm concerned about whether this would most likely cause: 1) a short circuit and permanent damage to the sensor itself, or 2) damage to the ECM. Currently, my only symptom is a check engine light and occasional erratic shifting. The diagnostic trouble code displayed is P0500. Given that the speedometer still functions normally, I'm wondering if the vehicle's electronic control module (ECM) has any built-in protection against such electrical faults.

Related fault codes
P0500
Comments (5)
Anonymous 2007-03-03 22:33

Could this be related to a farm tractor? Please provide your vehicle's year, make, and model for more accurate advice.

Anonymous 2007-03-04 08:26

2007 Toyota Corolla

Anonymous 2007-03-04 17:56

Does your speedometer work properly? Is the VSS a two-wire sensor? You can check its resistance. While I don't have specific data for your model, a Ford Focus VSS typically has a resistance between 1000 and 1250 ohms. It's possible that the ECM includes circuit protection and survived the electrical surge.

Anonymous 2007-03-04 18:33

Yes, the speedometer works fine. The only issue I'm experiencing is slight transmission shifting irregularities. My primary concern remains whether the ECM has been damaged by the power surge.

Anonymous 2007-03-04 18:49

I researched the P0500 code and found these potential causes to investigate: - Open or short circuit in the vehicle speed sensor wiring - Faulty vehicle speed sensor itself - Malfunctioning combination meter - ECM failure It's recommended to have the issue professionally diagnosed. Depending on your warranty, this may be covered. If a minor transmission problem exists now, it could escalate into a costly repair down the line.