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Testing Precautions

  1. Turn ignition off or disconnect battery for resistance tests. Disconnect engine speed/CKP sensor for compression tests, otherwise, high voltages and insulation damage to ignition coil(s), high-voltage distributor and/or 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(s) and ECM could be damaged.
  3. DO NOT  connect battery leads or test light to ignition coil terminal No. 1. ECM 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 No. 15), or ECM 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 ECM connectors. Electrostatic discharge may damage ECM.
  7. DO NOT  disconnect battery while engine is running. Reversed battery polarity could damage ignition or ECM. DO NOT  exceed a charging voltage of 16 volts (including when using a battery charger).
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