If you enjoy reading about cars and other related topics, we’d love to share our Auto Care Blog with you. At CARS of America, Inc., our highly trained auto mechanics deliver the very best in auto repair services through our two locations in Glenview. One way we accomplish that is in the time we take to help educate our customers so they feel confident making auto repair decisions. Our Auto Care Blog is just one way we meet that goal. Let us know if there’s a topic you’d like to hear more about!


Bad vehicle speed sensor affects your vehicle's anti-lock brakes

Your car’s “Check Engine” or “Service Engine Soon” light can flash on for more than 1,400 different reasons, and in the coming months, we’re going to share with you what some of those reasons are. The light is part of your vehicle’s on-board diagnostics (OBD) system and can indicate anything from a quick fix like a loose gas cap to a major repair like a catalytic converter.

Trouble code: P0500

This means the vehicle speed sensor is not reading the vehicle’s speed correctly.

Symptoms of a P0500 IAC Malfunction may include:

  • Anti-lock brake system reverts back to normal brakes. This is NOT a safety issue under non-slippery driving conditions.
  • The “anti-lock” or “brake” warning lamps on the dash may be lit (in addition to the check engine light).
  • The speedometer or odometer may not work properly (or at all).
  • Your vehicle’s RPM limiter may be decreased.
  • The shifting of an automatic transmission may become erratic.

Potential causes of a P0500 code include:

  • The vehicle speed sensor is not functioning properly.
  • There is a broken/frayed wire leading to the vehicle speed sensor.
  • The vehicle’s powertrain control module is not correctly configured for the actual tire size on the vehicle.

Possible solutions

  • Reset the code and see if it comes back.
  • Check all wiring and connectors that lead to the speed sensor.
  • Check the voltage at the speed sensor.
  • If everything looks OK, replace the sensor.

Is your check engine light on? Give CARS of America a call at 847-724-6724 or schedule an appointment.


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