Introduction To Diagnostic System

The diagnostic tests were designed to be used with a DRB-II Tester (C-4805). If this tester is unavailable, the "CHECK ENGINE" light can be used to retrieve fault codes. The "CHECK ENGINE" light cannot display any codes related to 88 diagnosis, blank displays or fault code 16. The light cannot show if the oxygen feedback system is operating from lean to rich or if idle motor and detonation systems are functioning. The light cannot perform actuation test, sensor test, or engine running test.

The DRB-II Tester (C-4805) can put the system into 5 different test modes. All 5 test modes must be used for a complete diagnosis of the system. The following information explains each test mode, codes corresponding to each mode, and method used to enter the test mode.