TEST PROCEDURES

NOTE: Perform the test procedures in the order in which they are presented here.

Ignition Coil Secondary Voltage Test

CRANK MODE

1. Connect a spark tester between the ignition coil wire and a good engine ground.
2. Crank the engine and check for spark at the tester.
3. Turn the ignition switch OFF.
4. If no spark occurs, check the following:
   1. Inspect the ignition coil for damage or carbon tracking.
   2. Check that the distributor shaft is rotating when the engine is being cranked.
5. If a spark did occur, check the distributor cap and rotor for damage or carbon tracking. Go to the Ignition Coil Secondary Voltage (Run Mode) Test.

RUN MODE

1. Fully apply the parking brake. Place the gear shift lever in Neutral (manual transmission) or Park (automatic transmission).
2. Disconnect the S terminal wire at the starter relay. Attach a remote starter switch.
3. Turn the ignition switch to the RUN position.
4. Using the remote starter switch, crank the engine and check for spark.
5. Turn the ignition switch OFF.
6. If no spark occurred, the problem lies with the wiring harness. Inspect the wiring harness for short circuits, open circuits and other defects.
7. If a spark did occur, the problem is not in the ignition system.

Spark Timing Advance Test (1994 B Series Pick-up with 3.0L engine)

Spark timing advance is controlled by the engine control module. This procedure checks the capability of the ignition module to receive the spark timing command from the engine control module. The use of a volt/ohmmeter is required.

1. Turn the ignition switch OFF.
2. Disconnect the pin-in-line connector (SPOUT connector) near the TFI module.
3. Start the engine and measure the voltage, at idle, from the SPOUT connector to the distributor base. The reading should equal battery voltage.
4. If the result is okay, the problem lies within the EEC-IV system.
5. If the result was not satisfactory, separate the wiring harness connector from the ignition module. Check for damage, corrosion or dirt. Service as necessary.
6. Measure the resistance between terminal No. 5 and the pin-in-line connector. This test is done at the ignition module connector only. The reading should be less than 5 ohms.
7. If the reading is okay, replace the TFI module.
8. If the result was not satisfactory, service the wiring between the pin inline connector and the TFI connector.