Ignition Timing Connector: Description and Operation

Ignition Timing Adjustment Terminal:

PURPOSE
The ignition timing adjustment connector returns timing to the initial setting (Base Timing) to allow for accurate adjustment.

LOCATION
On the firewall behind the battery next to the fuel pump test connector

OPERATION
The ignition timing adjustment signal, is manually grounded by the technician to remove the ECM's control of the ignition timing. This is needed to adjust the base ignition timing setting. If the circuit becomes grounded at any time, ECM control of the ignition system is disabled, the "Malfunction Indicator Light" will come on, and the ECM will store a trouble code. Operation of the vehicle under these conditions can result in loss of power and engine overheating.