NOTE: Although this information applies basically to Subaru models, the same principle applies to Toyota models with resistors or resistance wires.

Turn ignition switch "ON". Connect negative lead of a voltmeter to ground and positive lead (in turn) to each of the resistor terminals "a" and "b". One reading should be battery voltage, the other reading should be one half that voltage. If so, proceed to step 10.
If there was no voltage at either terminal in step 1, check wiring harness, connector, ignition switch and fuse between battery and resistor. Check for broken wires, poor connections, and battery condition.
If there was voltage at only one of the resistor terminals in step 1, turn ignition switch "ON" and disconnect lead wire from terminal having no voltage. Check resistor terminal for voltage. If none, replace resistor. If voltage now exists, check wiring harness between resistor and positive terminal of ignition coil for short circuit. Repair or replace as necessary.
If there was voltage at both terminals, but one was not about one-half battery voltage, turn ignition switch "ON". Connect voltmeter negative lead to ground and positive lead to ignition coil negative terminal. Reading should be battery voltage.
If not, turn ignition switch "ON" and connect voltmeter negative lead to ground and positive lead to ignition coil positive terminal. Reading should be battery voltage. If not, replace ignition coil. If battery voltage is shown, check wiring harness between resistor and ignition coil positive terminal. Check for broken wires, poor connections and repair as necessary.
If voltage at ignition coil negative terminal in step 4, was battery voltage, turn ignition switch "OFF". Using an ohmmeter set in the x1 range, measure resistance between ignitor side and ground. Resistance should be less than 0.5 ohm. If not, check ground wire for proper contact at regulator bracket.
If resistance was less than 0.5 ohm in step 6, proceed to the next step, step 8).
Turn ignition switch "OFF". Disconnect 2-pin (Toyota) or 3-pin (Subaru) distributor connector. Disconnect high tension wire at distributor and hold it about 1/4" (6 mm) from engine block. Turn ignition switch "ON". Check if spark jumps when a small voltage (1-6 volts) is applied intermittently on terminals "1" (pink wire) and "2" (white wire) on ignitor side of connector.

Fig 1: Conducting Tests at Distributor Connector (Subaru Shown)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Ignition System Test

Use the Manual With the Right Hardware

When to See a Mechanic

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