System Testing (Without EZK Tester)
To test EZK ignition system (non-turbo models only)1. Check the basic components subject to wear and electrical breakdown.
Test the condition of the spark plug wires and the ignition rotor by testing the resistance of each component.
Ignition rotor 1,000 ohms
Coil high tension lead
(complete with end connectors) 500-1,500 ohms
Spark plug leads
(complete with end connectors) 2,000-3,000 ohms
2. Test the knock sensor output signal.
Remove the harness connector from the EZK control unit. Using a digital voltmeter (set to VAC scale), connect it to terminal 12 and 13 of the control unit connector. Gently tap on the knock sensor mounting bolt. The voltmeter should register a small voltage and the reading should vary depending on the intensity of the tap.
Note:
- The knock sensor is mounted to the engine block between cylinders no.2 and 3, below the intake manifold.
- Procedure step 1 checks both the knock sensor and the wiring to the control unit. It the knock sensor does not respond to the tapping, remove the sensor and its connector. Then connect the voltmeter directly to the sensor tenninals and repeat the above test. It the sensor now tests good, check the wiring from the sensor connector to the EZK control unit. If the sensor does not respond, it is faulty and should be replaced.
3. Check for power to the EZK control unit.
Unplug the connector from the EZK control unit and connect a voltmeter (VDC scale) between terminal 6 (+) and 20 (-) of the connector. With the ignition on, there should be battery voltage. Turn the ignition oft and reconnect the connector. If no faults are found proceed to the next step. If voltage is not present, use the wiring diagrams to check for wiring faults.
4. Check for power to the amplifier.
Peel back the boot on the amplifier harness connector. Connect a voltmeter between the terminal 4 (+) and 2 (-) on fender-mounted amplifiers or between terminals 3 (+) and 2 (-) on coil-mounted amplifiers. With the ignition on, there should be battery voltage. If no faults are found proceed to the next step. If voltage is not present, use the wiring diagrams to check for wiring faults from the ignition switch.
Note: On fender-mounted amplifiers, the amplifier should be removed from its mountings to access the harness connector.
5. Check for power to the coil.
Connect a voltmeter between terminal 15 and ground on conventional coils or between terminal 3 and ground on coils with amplifier. With the ignition on, there should be battery voltage. If no faults are found proceed to the next step. If voltage is not present, use the wiring diagrams to check for wiring faults from the ignition switch.
6. Check the coil primary and secondary circuit resistance.
With the ignition off, remove all wires from the coil. Measure the resistance of the coil circuits as shown.
Primary resistance (terms 1 & 15 or 4 & 3) 0.5 - 0.9 ohms
Secondary resistance (center tower and term 1 or 4) 7200 - 8200 ohms
If any faults are found the coil is faulty and should be replaced. If no faults are found, proceed to the next step. Reconnect the wires to the coil.
7. Check the amplifier switching function.
Connect the voltmeter between coil terminals 15 (+) and 1 (-) on conventional coils or between terminal 3 (+) and 4 (-) on coils with integrated amplifier. Turn the ignition on. The voltage should rise to about 6 volts (DC) and then drop to 0 volts within 1 to 2 seconds. It any faults are found, replace the amplifier. If no faults are found proceed to the next step.
8. Check the pulse signal from the EZK control unit to the amplifier.
Peel back the rubber boot on the control unit connector. Connect a voltmeter between the terminals 5 (+) and 2 (-) on fender-mounted amplifiers or between terminals 4 (+) and 2 (-) on coil mounted amplifiers. While operating the starter, there should be an oscillating voltage (pulses between 0 and 8 volts (DC), average of 2.8 volts). If no faults are found, the amplifier is faulty and should be replaced. If there is no pulse, proceed to the next step.
9. Check the Hall sensor signal to the EZK control unit.
Peel back the rubber boot on the EZK control unit connector. Connect a voltmeter between terminal 24 (+) and 20 (-). Turn the ignition on and slowly turn the engine over by hand. The voltage should oscillate between 0.4 volts (DC) (or less) and 3.0 volts (or higher). If no faults are found, the EZK control unit is probably faulty and should be replaced. If any faults are found, proceed to the next step.
Caution: Turn the engine over only in the direction of normal rotation. Otherwise damage to the timing chain and its components may result. To determine normal rotation, put the car in gear and rock the car forward, noting the rotation of the ignition rotor, the flywheel, or a belt-driven component. As an alternative, briefly operate the starter.
Note: The engine can be turned over using a wrench on the crankshaft pulley.
10. Check for voltage to the Hall sensor.
Working from the rear of the EZK control unit connector, connect a voltmeter between terminal 4 (+) and 10 (-). With the ignition on, there should be battery voltage. If no faults are found, the Hall sensor is faulty and should be replaced. If voltage is not present, the EZK control unit is faulty.
Note: On all 1986-1988 cars, the Hall sensor is in the distributor. On 1989 and later cars, the Hall sensor is mounted behind the crankshaft pulley. Hall sensor replacement procedures are described below.
Note:
If on 1986 and 1987 models, all electrical checks are as spectied but the car still does not start, check the ignition pulse amplifier on the main fuse relay panel. This relay-like amplifier is designed to "amplify" the tachometer signal for more reliable control of electronic components affected by the ignition system (LH fuel injection, fuel pump control, etc.). To check the amplifier, simply remove it from its socket. Then using a jumper wire, jumper the fuse/relay panel sockets corresponding to relay terminals TD-I and TD-O. Try to start the engine. If the engine now runs, replace the pulse amplifier.