Ignition System: Testing and Inspection

If a vehicle does not start, the first step is to check for secondary ignition voltage:
- Disconnect one spark plug wire at spark plug end.
- Connect a known good spark plug to plug end.
- Hold spark plug with insulated pliers to ground and crank engine.
- A bright blue spark should be present when cranking the engine.

NOTE: If no spark is present, continue with checks. If spark is present, check air intake/fuel system.





Check voltage supply to distributor
- Remove connector from distributor and connect a voltmeter to the outer terminals. With the key on, the voltmeter should show battery voltage.

NOTE:
- If there is no voltage, before going to the next step, check the wire harness from the distributor to the control unit.
- If there is voltage, check voltage supply to ignition coil.





If there is no voltage at the distributor connector, check for voltage at the control unit.
- Remove the connector from the control unit and connect a voltmeter between terminals 2 & 4.
- With the key on. the voltmeter should show about 12 volts. If the voltage is OK, then the control unit is the cause.
- If no voltage, repair wiring and recheck.

Note: Location of Hall ignition ECU
- 4000 Above glove box
- 5000 Behind left kick panel





Checking ignition control unit
- Remove connector from distributor.
- Connect positive lead of voltmeter to terminal 15.
- Connect negative lead to terminal 1 of ignition coil.
- Turn ignition on.
- Voltmeter will show voltage and must drop to 0 within 1 or 2 seconds.
- If the voltage does not drop, replace the control unit.
- Lightly tap center wire from disconnected connector for the Hall sender, to ground.
^ Displayed voltage must rise to a minimum of 2 volts for a short time. If not replace Hall control unit.





Hall sending unit checking
- Remove protective cover from connector on Hall ignition E.C.U.

Note:
Location of Hall ignition E.C.U. 4000 - Above glove box 5000 - Behind left kick panel

- Connect US 1119 to terminals 3 and 6 and set to 20 DCV scale.
- Actuate starter
^ Specified value voltage display If voltage is present, check the ignition coil. If no voltage, check Hall sending unit.





- remove Hall sending unit connector from distributor.
- connect voltmeter to terminals 1 and 3 of connector D.
- switch ignition ON
^ specifications: minimum 9 V

If specifications NOT OK
- check for open circuit in wiring to Hall sending unit according to current flow diagram

If specification OK
- switch ignition OFF
- reinstall connector on distributor
- move back protective cover on Hall sending unit connector
- connect voltmeter across wires for terminals 1 and 2
- remove distributor cap, rotor, and dust cover
- switch ignition ON

Note: Distributor cap retaining clips must not interfere with trigger wheel unit during test.





- turn crankshaft until trigger wheel blocks Hall sender
- check voltage reading
^ specification: minimum 4.0 V





- turn crankshaft until air gap is fully aligned with Hall sending unit
- check voltage reading
^ specification: 0-0.5 V
- switch ignition OFF

If specification NOT OK
- replace Hall sending unit

If specification OK
- check wiring for open circuit between Hall sending unit and control unit connector





Check ignition coil
- Remove all of the wires from the coil and connect an ohmmeter between terminals:
^ 15 and 1 - resistance should be 0.52 to 0.76 ohms





^ 4 and 1 - resistance should be 2.4 to 3.5k ohms.