Accessing and Reading Diagnostic Trouble Codes

Fig. 2 ALDL connector terminal identification:

Fig. 3 Trouble code identification:

Connect a jumper wire between ALCL-ALDL connector terminals A and B, Fig. 2. After jumper leads are connected, the ``Check Engine'' lamp will flash appropriate trouble codes. The codes are indicated by a pulsing of the lamp. One pulse followed by a short time lapse, then two pulses would indicate a code 12 and so on. If only one trouble code is stored, the code will repeat continuously until test leads are disconnected. If more than one trouble code is stored, each code will repeat three times, starting with the lowest, then proceed to the next code. After all codes have been shown, the pattern will repeat itself. Refer to Fig. 3, for light pulse indications and trouble code identification.