Without Scan Tool

When the PCM senses an abnormality in the input or output systems, the [D4] indicator light in the gauge assembly will blink. When the Service Check Connector (2P) (located under the dash on the passenger side) is connected with the special tool as shown, the [D4] indicator light will blink the Diagnostic Trouble Code (DTC) when the ignition switch is turned ON.




Codes 1 through 9 are indicated by individual short blinks. Codes 10 and above are indicated by a series of long and short blinks. One long blink equals 10 short blinks. Add the long and short blinks together to determine the code. After determining the code, refer to Trouble Code Descriptions. DTC List - Transmission Control Systems