Actuator Test Mode (ATM)

NOTE: This test can only be performed with the Diagnostic Readout Tool (C-4805).

Remove coil wire from cap and place 1/4" from good ground source. Ensure distance does NOT exceed 1/4" or power module damage may result. Remove air cleaner hose from throttle body.
Press ATM button on Diagnostic Readout Tool. Observe the following: 3 sparks from coil wire to ground, listen carefully for 2 AIS motor movements (1 open and 1 close).
With ATM button still depressed, disconnect Gray distributor synchronization connector. Install a jumper wire between pins 2 and 3 of the synchronization connector.
Listen for click which indicates 1 set of injectors has been activated. Remove jumper wire and second set of injectors will be activated. Remove jumper wire and reconnect connector.
ATM capability is canceled 5 minutes after ignition switch is turned on. To reinstate ATM test, cycle ignition switch on and off 3 times, ending with ignition switch in "ON" position.
When ATM button is depressed, fault Code 42 is generated because the ASD relay is by-passed. DO NOT use this code for diagnostics after ATM test mode has been performed.
The ATM test mode checks 3 categories of operation. When the coil fires 3 times, the following is indicated: coil is operational, logic module and power modules are operational, and interface between modules is working properly.
When open and close movements of the AIS are heard, this indicates AIS motor is operating properly. When jumper wire is installed, the following is indicated: fuel injectors operational, fuel pump operational, and fuel lines intact.
The EFI system must be evaluated using all the information found in the system and ATM tests.