Ignition System - Direct Nissan Pulsar N13

DESCRIPTION & OPERATION

The Direct Ignition system uses one coil per cylinder. A crank angle sensor monitors engine speed and piston location. Signals created by the crank angle sensor are sent to the Electronic Control Unit (ECU). The ECU then delivers ignition signals to the power transistor to control ignition.

Scheme 1

IGNITION COIL RESISTANCE

1. Using ohmmeter, check resistance between terminals "A" and "B". (Scheme 2) Resistance should be.7 ohms.
2. Check resistance between terminal "C" and spark plug connector end. Resistance should be 7000 ohms. Replace coil if not within specification.

IGNITION COIL POWER SOURCE

1. Turn ignition on. Using voltmeter, check voltage between terminal "B" and ground of ignition coil plug. (Scheme 2) Battery voltage should exist.
2. If battery voltage is not present, check power transistor relay. If battery voltage was present, turn ignition off. With an ohmmeter, check continuity between terminal "A" and ground. (Scheme 2) Continuity should exist. Repair harness or connector if no continuity is present.

Scheme 2

POWER TRANSISTOR RELAY

1. Connect a 12-volt power source to terminals No. 1 and 2. (Scheme 3) Using ohmmeter, check continuity between terminals No. 3 and 5. Continuity should exist.
2. Disconnect power source and recheck continuity. No continuity should exist. Check harness and connectors. If harness and connectors are okay, replace power transistor relay.

Scheme 3

Note. For more information on Direct Ignition System, see NISSAN ECCS article in COMPUTERIZED ENGINE CONTROL section.