For 1990-2009 cars

This information refers to Domestic and Export calibration packages. Use the DTCs that only apply to your specific Regular Production Option (RPO). Each DTC is directly related to a diagnostic test. The DTC sets based upon the DTCs individual running and setting criteria.

The following are the types of DTCs and their code characteristics:

#### Type A

• | Emissions related

• | Requests illumination of the malfunction indicator lamp (MIL) on the first trip with a fail

• | Stores a History DTC on the first trip with a fail

• | Stores a Freeze Frame on the first trip with a fail

• | Stores a Failure Record

• | Updates the Failure Record the first time the test fails each ignition cycle

#### Type B

• | Emissions related

• | The code is enabled after the first trip with a fail

• | The code is disabled if the second consecutive trip passes

• | Requests illumination of the MIL on the second consecutive trip with a fail

• | Stores a History DTC on the second consecutive trip with a fail

• | Stores a Freeze Frame on the second consecutive trip with a fail

• | Stores a Failure Record when the first test fails

• | Updates the Failure Record the first time the test fails each ignition cycle

#### Type C1

• | Non-emissions related

• | Requests illumination of the Service Lamp, not the MIL, or the service message on the first trip with a fail

• | Stores a History DTC on the first trip with a fail

• | Does not store a Freeze Frame

• | Stores a Failure Record when the test fails

• | Updates the Failure Record the first time the test fails each ignition cycle

#### Type C0

• | Non-missions related

• | Does not request illumination of any lamps

• | Stores a History DTC on the first trip with a fail

• | Does not store a Freeze Frame

• | Stores a Failure Record when the test fails

• | Updates the Failure Record the first time the test fails each ignition cycle

#### Type X

• | Diagnostics that are coded in the software, but will not run for non-OBD2 export vehicles

• | Some domestic vehicles use DTCs

• | Even though codes are not stored, the DTC Type Table can still be used as a resource when diagnosing problems with systems that are associated with the Type X DTCs

If a system is malfunctioning and the associated Type X DTC has been disabled, it may be beneficial to use the diagnostic table as a guide to aid in diagnosis. Many of the DTC tables include a functional check of the system that may pinpoint a problem. However, it is important to remember that the DTC tables are specifically designed for use only when a DTC is set. Therefore, a thorough understanding of the normal operation of the system being diagnosed is necessary, and use of the tables for this purpose is at the discretion of the technician.