How to Use the Diagnostic Readout Box

The diagnostic readout box is used to put the on-board diagnostic system in three different modes of testing as called for in the driveability test procedure. The following are instructions on how to do this:
1. Connect tester to diagnostic connector located in engine compartment near passenger side strut tower.
2. Start engine, if possible, move transmission selector through ranges and cycle A/C compressor on and off, then stop engine.
3. Turn ignition switch on, off, on, off and on within 5 seconds.
4. Check engine lamp should light for 3 seconds, then go out and stored fault codes will be displayed on tool.

The diagnostic readout tool C-4805 must be used to enter the system into one of three test modes:
A. DIAGNOSTIC TEST MODE
B. CIRCUIT ACTUATION TEST MODE (ATM)
C. SWITCH TEST MODE

These three test modes are required to diagnose the system.