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Spark Test

  1. Disconnect coil wire from distributor(s). Using insulated pliers, hold end of coil wire 1/2" from ground. Crank engine for 1-2 seconds. If spark is not present, go to next step. If spark is present, replace faulty distributor rotor, cap, wires or spark plugs as necessary.
  2. Turn ignition off. Check for poor electrical connections at ignition coil, ignitor and distributor. If connections are okay, check resistance of coil wire and spark plug wires. Maximum allowable resistance is 25,000 ohms per wire.
  3. If resistance is okay, turn ignition on. Disconnect ignition coil connector. Check voltage at positive terminal (Black/Orange wire) of ignition coil connector. If battery voltage is not present, check for open or grounded Black/Orange wire or open fuse (on SC300, also check for faulty ignition main relay).
  4. If battery voltage is present, turn ignition off. Measure ignition coil resistance. See IGNITION COIL RESISTANCE  table. If resistance is not within specification, replace ignition coil.
  5. If resistance is within specification, check resistance across terminals of the following distributor sensor. See DISTRIBUTOR SENSOR RESISTANCE  table.
    • Distributor pick-up coil. See Fig 1.
  6. If resistance is not within specification, replace distributor housing. If resistance is within specification, go to next step (SC300).
  7. Measure air gap of pick-up coils G1, G2 and NE. See Fig 4. If air gap is within specification, go to next step. If air gap is not within specification, replace distributor.
IGNITION COIL RESISTANCE - Ohms

Application Primary Secondary
Cold (1) .21-.33 6400-11,100
Hot (2) .27-.39 8200-13,000
(1) Coil temperature of 14-122°F (-10-50°C).
(2) Coil temperature of 123-212°F (51-100°C).
DISTRIBUTOR SENSOR RESISTANCE

Application Ohms
SC300 (Pick-Up Coils)
Cold (1)
Between Terminals G1 & "G-" 125-200
Between Terminals G2 & "G-" 125-200
Between Terminals NE & "G-" 155-250
Hot (2)
Between Terminals G1 & "G-" 160-235
Between Terminals G2 & "G-" 160-235
Between Terminals NE & "G-" 190-290
(1) Sensor temperature of 14-122°F (-10-50°C).
(2) Sensor temperature of 123-212°F (51-100°C).
DISTRIBUTOR PICK-UP COIL AIR GAP (SC300) (1)

Application In. (mm)
SC300 .008-.016 (.20-.40)
(1) Not adjustable. If gap is incorrect, replace distributor housing.
Fig 1: Checking Pick-Up Coil Resistance (SC300)
G94D45107Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 2: Checking Right Camshaft Sensor Resistance (Left Is Similar)
G93B78189Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 3: Checking Crankshaft (Engine Speed) Sensor Resistance
G90E18881Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Fig 4: Measuring Pick-Up Coil Air Gaps (SC300)
G94E45108Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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