Engine Light On

What is an ECU?

Check Engine indicators

Different types of Check Engine indicators

Modern cars have a high number and vast array of Electronic Control Units (ECU’s).

The engine has an Engine Electronic Control Unit (or Engine Computer), which is designed to control every aspect of the engines running, from ignition timing, fuel injection, emissions and so on.

Your engine has a wide variety of sensors and actuators that provide inputs and outputs to the Engine Electronic Control Unit (or Engine Computer). The engine computer is constantly monitoring and adjusting levels to keep the air / fuel mixture at around 14.7 to 1, which is the ideal air fuel ratio for most engines in modern cars.

So why is my Check Engine light flashing?

If any sensor or actuator goes out of range by approximately 1.5 times its designed tolerance, then the self diagnostic routines in the cars engine computer store a fault code, or trouble code. This will generally always bring a warning light on the dash most commonly called the Check Engine Light (CEL) or Malfunction Indicator Light (MIL Light).

The Check Engine Light (CEL) or Malfunction Indicator Light (MIL Light) are designed to warn the driver that there is a fault with the vehicle that needs attention.

Therefore if you have a Check Engine Light (CEL) or Malfunction Indicator Light (MIL Light) light glowing on your dash or coming on intermittently while driving it is very important that you get the fault codes and live data read as soon as possible to avoid possible future, more costly damage.

Diagnosing your engine fault

Grimmer Motors uses a range of the best, state of the art scan tools that will read the fault codes and live data from your vehicle. Our skilled, trained and qualified technicians combined with our leading edge analysis technology mean that we will quickly and easily read the fault codes and live data from your vehicle, provide you with a diagnostic printout, and repair the faults as required. Call us now to book in your “scan” to read your engine codes.

Please Note: Electronic Tests depend on the vehicle technology and may not be possible on some vehicles.

Conveniently located in Fairfield, Grimmer Motors have been providing quality service to Hamilton since the company was established in 1934. When you receive battery-related services through Grimmer Motors, you can trust our fully qualified mechanics to safely and efficiently service your vehicle, advising you before further repair work is conducted.


Live/work in any of the following areas? Grimmer Motors could be extra convenient for you.Fairfield

  • Fairview Downs
  • Enderly
  • Claudelands
  • Peachgrove
  • Hamilton East
  • Chartwell
  • Chedworth
  • Central Hamilton
  • Forest Lake, Beerescourt
  • Frankton
  • Melville
  • Waikato