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Testing Precautions

  1. Turn ignition off or disconnect battery for resistance tests. Disconnect engine speed/reference mark sensor for compression tests, otherwise, high voltages and insulation damage to ignition coil, high-voltage distributor and ignition leads may result.
  2. DO NOT  connect a capacitor to ignition coil terminals. DO NOT  connect ignition coil terminal No. 1 to ground. Ignition coil and DME control unit could be damaged.
  3. DO NOT  connect battery leads or test light to ignition coil terminal No. 1. DME control unit will be damaged. DO NOT  disconnect ignition lead from ignition coil secondary terminal during engine operation.
  4. Avoid voltage flashover from ignition coil secondary terminal to ignition coil primary terminals (No. 1 and 15), or DME control unit may be damaged.
  5. During testing, secondary circuit of ignition system must be suppressed at all times with 4000-ohm resistance (1000-ohm distributor cap suppression resistor; 3000-ohm spark plug lead suppression resistors).
  6. Always turn ignition off or disconnect battery before disconnecting ignition or DME control unit connectors. Electrostatic discharge may damage DME control unit.
  7. DO NOT  disconnect battery while engine is running. Reversed battery polarity could damage ignition or DME control unit. DO NOT  exceed a charging voltage of 16 volts (including when using a battery charger).
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