Ignition Timing Reference Sensor (CIS Digital Control)

Sensor is located next to engine RPM speed sensor and detects rotation of a pin located 460 degrees BTDC. Sensor sends reference signal to control unit when TDC occurs for number one and number 4 cylinder.

The hall effect switch, located in ignition distributor, produces one signal for each revolution of the distributor. This signal occurs just before TDC of number one cylinder and is used to determine which signal from the ignition timing reference sensor is the actual TDC signal for number one cylinder. Do not rotate distributor to set base timing.