Ignition System - Hitachi Electronic Nissan 200SX S12

DESCRIPTION

Two ignition systems are used in Nissan models. The principle of operation on both systems is the same. Both use an electronic distributor, an IC ignition unit, ignition coil(s), battery and wiring harness. All models have a fusible link between battery and ignition switch. The ignition system used on Stanza, and 200SX 4-cylinder models uses 8 spark plugs.

On Stanza models, the IC ignition unit is located inside the distributor. The IC ignition unit may have a 4-pin connector (200SX and Stanza). The IC ignition unit internal circuits vary from model to model.

OPERATION

All distributors are equipped with a reluctor and stator. The reluctor is mounted on the rotor shaft assembly. It turns with the distributor shaft inside the stator.

As each reluctor tooth approaches and passes the stator teeth, the magnetic field changes, creating an electrical signal in the pick-up coil. The pick-up coil is combined with the IC ignition unit on Stanza, and 200SX models. This signal is received and processed by the IC ignition unit.

The IC ignition unit turns on and off current flow to the ignition coil primary circuit. When current to the primary is turned off, a high voltage surge is created in the secondary circuit, which fires the spark plug.

Ignition timing is controlled by the relationship of the reluctor to the stator. All circuits are contained in one IC ignition unit. Failure of any circuit requires replacement of entire IC ignition unit.

AIR GAP

When installing reluctor and stator or checking air gap, loosen screws and center stator around reluctor. There should be equal air gap. (Scheme 1) Tighten stator screws. Standard air gap is.012-.020" (.30-.50 mm).

Checking Reluctor-to-Stator Air Gap. Scheme 1

SYSTEM SPARK TEST

1. If engine cranks but does not start, go to next step. If engine runs erratically, check ignition timing and adjust if necessary. If timing is okay, go to next step.
2. Disconnect any spark plug wire and insert a used spark plug whose threads have been cut off. (Scheme 2) Hold spark plug about 1/4" away from engine block. Crank engine and check for sparks at gap.
3. If regular sparks occur, IC ignition system is okay. Check spark plugs and/or fuel system. If no sparks occur, check air gap. See «ADJUSTMENTS»(/nissan/200sx/s12-1983-1989/remont/ignition-system/#ignition-system-hitachi-electronic). If okay, perform following tests in sequence.

System Spark Test. Scheme 2

BATTERY VOLTAGE TEST

1. Turn ignition off. Connect positive lead of voltmeter to battery positive terminal. Connect negative lead to battery negative terminal. Read and record battery voltage. If below 11.5 volts, battery charging or starting system is faulty.
2. With ignition off and voltmeter still hooked to battery, remove coil wire from distributor and connect to ground. Crank engine and record cranking voltage. If voltage reading is less than 9.6 volts, battery charging or starting system is faulty.

SECONDARY WIRING TEST

Connect an ohmmeter, in turn, to each spark plug wire. Attach one lead to terminal inside distributor cap and other lead to end of wire. Resistance reading should be less than 30,000 ohms. If resistance is higher, replace spark plug wire(s) and/or distributor cap.

Primary Resistance

1. Turn ignition off and disconnect coil. Set ohmmeter to x1 range. Connect ohmmeter leads to coil primary terminals. Stanza and 200SX reading should read .84-1.02 ohms.
2. If reading is correct, but engine will not start, check ignition switch and wiring from switch to coil and IC ignition unit. If reading is incorrect, replace ignition coil.

Secondary Resistance

Turn ignition off and disconnect coil. Set ohmmeter to x1000 range. Connect one lead to coil negative terminal and other lead to coil tower. Resistance for Stanza and 200SX reading should be 8000-12,400 ohms. If not, replace ignition coil.

POWER SUPPLY CIRCUIT TEST

Connect voltmeter positive lead to "B" (Black/White wire) terminal. (Scheme 3) Connect voltmeter negative lead to side of distributor housing. Turn ignition on. If reading is less than 11.5 volts, check wiring from ignition switch to IC ignition unit.

Stanza & 200 SX Power Supply Test. Scheme 3

POWER SUPPLY CIRCUIT CRANKING TEST

1. Remove high tension coil wire from distributor and ground it. Connect voltmeter as outlined in «POWER SUPPLY CIRCUIT TEST»(/nissan/200sx/s12-1983-1989/remont/ignition-system/#ignition-system-hitachi-electronic__power-supply-circuit-test). (Scheme 3) Crank engine and note voltmeter reading.
2. If voltage reading is more than one volt below battery cranking voltage and/or is below 8.6 volts, check ignition switch and wiring from switch to IC ignition unit.

IGNITION PRIMARY CIRCUIT TEST

1. Attach a voltmeter negative lead to side of distributor.
2. On Stanza, and 200SX, connect voltmeter positive lead to "I" (Red wire) terminal and then to "E" (Blue wire) terminal of IC ignition unit connector. (Scheme 4)
3. Turn ignition on. Voltage reading should be 11.5-12.5 volts. If reading is below 11.5 volts, check coil primary resistance if not previously done. If voltage is correct, go to «IC IGNITION UNIT GROUND CIRCUIT TEST»(/nissan/200sx/s12-1983-1989/remont/ignition-system/#ignition-system-hitachi-electronic__ic-ignition-unit-ground-circuit-test).

Ignition Primary Circuit Test. Scheme 4

IC IGNITION UNIT GROUND CIRCUIT TEST

1. Connect voltmeter negative lead to battery negative terminal. On others, connect positive lead as shown. (Scheme 5) Pull high tension wire from distributor cap and ground it.
2. Crank engine and note voltmeter reading. If reading is.5 volts or less, replace IC ignition unit. If reading is more than.5 volts, check distributor ground wiring from chassis to battery, including battery connections.

Stanza & 200SX IC Ignition Unit Ground Circuit Test Connect positive lead as shown. Scheme 5

DISASSEMBLY

1. Remove distributor cap and rotor. Remove harness and vacuum diaphragm from housing. Using 2 screwdrivers, pry reluctor from rotor shaft. Use care not to damage teeth. Remove roll pin from reluctor.
2. Remove breaker plate and IC unit. (Scheme 6) Remove setter, stator and magnet from breaker plate. Knock out roll pin and remove pinion. Remove shaft assembly. Remove packing and rotor shaft set screw. Remove weights and springs.

Hitachi Distributor Used on Stanza & 200SX. Scheme 6

REASSEMBLY

1. To assemble, reverse disassembly procedure. Clean surfaces of IC ignition unit and distributor before assembling. Ensure pick-up coil leads (if equipped) are securely attached to IC ignition unit terminals.
2. Align match marks so parts are assembled in original positions. Check air gap before tightening stator screws. See procedures under «ADJUSTMENTS»(/nissan/200sx/s12-1983-1989/remont/ignition-system/#ignition-system-hitachi-electronic). Drive in roll pin with cut-out as shown. (Scheme 7) Check governor operation before installing distributor.
3. Use new roll pin in pinion or collar. Grease top of rotor shaft, shaft bearing metal, springs and frictional surface of weights and breaker plate. Ensure vacuum and centrifugal advance mechanisms are working properly.

Installing Roll Pin in Reluctor Note position of roll pin cut-out. Scheme 7

See also:
• ADJUSTMENTS
• POWER SUPPLY CIRCUIT TEST
• IC IGNITION UNIT GROUND CIRCUIT TEST