- 1). Crank your Mustang GT's engine to activate the car's electronics. This will also display the warning light you are trying to identify, if it is currently triggered.
- 2). Look beneath the speedometer needle. One of the warning lights under this needle is the TPMS (Tire Pressure Monitoring System) warning light. This light shows an exclamation point icon. If you see this light, it means one or more of your tires are under inflated.
- 3). Inspect the area beneath the speedometer needle again. There is another warning light in this section of the cluster known as the "Check Engine Light." The icon for this light is the outline of an engine. If you see this light, there may be a malfunction with your vehicle's emission control system. A common cause for this light is a bad O2 sensor.
- 4). Inspect the center of the odometer cluster. In the center you'll find the fuel gauge and the temperature gauge. In this part of the cluster, there are several warning lights. If you see a "Battery" icon, there may be a problem with the charging system. If you see the "Thermometer" icon, there may be a problem with the engine cooling system. If you see a "Gas Tank" icon, the Mustang is low on fuel. If you see an "Oil Can" icon, your Mustang GT may be low on oil.
- 5). Inspect the far right edge of the instrument cluster within the RPM gauge. In here are two warning lights. If you see a "Wrench" icon, the Mustang is due for its scheduled service (such as an oil change). If you see a "Padlock" icon, there may be an issue with the Mustang's security system.
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